**2.1 Main 2020–2030 megatrends and how the world has responded to the crisis and the crisis period and later too**

The following megatrends will dominate the next 10 years:

As a result, humans are heading in the following directions in the face of these quantitative and qualitative changes, which are the megatrends that will influence every part of humanity's lives for at least the next 50 years:

*A Worldwide Regression Analysis of Relations between Creativity, Innovation, and Quality… DOI: http://dx.doi.org/10.5772/intechopen.111744*

#### **2.2 Factors of production**

The inputs utilized in the production process for financial gain are included or described as factors of production. As previously noted, the factors of production in this essay are as follows: (1) land, (2) labor, (3) capital, (4) innovation, and (5) entrepreneurship. (Although some authors include entrepreneurship innovation, innovation is not a sole attribute of entrepreneurs, but of employees and other individuals who are not involved in business activities as well).

It is clear, the cyclical nature of the economy and the cyclical use of production factors have been and continue to be closely related to world history regarding factors of production since preparing the paper carefully followed the developments of the global economy for at least the last 40 years and read the literature on the history of the development of the global economy for at least the last 600 years.

The use of physical factors—land, labor, and capital—that have always been regarded as fixed factors of production was 1 cycle that is currently understood. The other cycle is the use and management of creativity, innovation, and entrepreneurial skills, knowledge, and competencies—that are regarded as non-fixed factors of production. It has been the cycle of use, exploitation, and management of land, labor, and capital that has predominated in some historical and economic development periods, while it has been the cycle of use and management of skills, knowledge, and competencies related to creativity, innovation, and entrepreneurship in other historical and economic development periods. The stages of applying these components, which are the stages of entry, growth, maturity, and decline, are what lead to all of this. One cycle enters the entry phase if it is in the decline phase, and the other cycle enters the endpoint phase if it is in the peak maturity phase.

Nowadays, there is a significant quantity of territory (land) in almost every nation that is not utilized, exploited, or managed. Unemployment is extremely high everywhere in the world and primarily affects young people. A lot of free money is also available around the globe, both in banks and in people's pockets, but it is not being invested.

Therefore, it is evident and simple to see that the cycle of use, exploitation, and management of land, labor, and capital is in decline or may have even reached the end of the decline phase. In contrast, the cycle of exploitation, use, and management of creativity, innovation, and entrepreneurial skills is rising or even at its peak. It is difficult to predict how long this phenomenon will last, during which the cycle of the use of fixed factors of production will be declining and the cycle of non-fixed factors

of production will mature. However, one thing is certain: When 1 cycle reaches its growth peak, the other cycle reaches its endpoint, and vice versa.

One of the key components for increasing productivity and economic growth has been, is, and will continue to be the rapid technological advancement and the accumulation of skills, knowledge, and competencies; in this regard, systems and networks that effectively and efficiently disseminate information, skills, knowledge, and competencies are crucial. For this, policies about education, science, industries, and technologies as well as incentives for investments in research and development, ongoing training, support for systems of creativity, innovation, and quality management, as well as infrastructure for these purposes are necessary [3, 4].

#### **2.3 Creativity**

Years of quality management experience have shown that creative (1) processes, (2) procedures, (3) goods, (4) services, (5), and so on, are an important components of creativity or contain it [5–7]. This demonstrates, in essence, that creativity is what initiates first and establishes the conditions for inventive activities to occur, acting as a continuous mental and psychological process for problem identification and solution selection [8].

The process of creativity, which consists of several stages and is characterized by a thinking process where (1) fluid, (2) flexible, (3) original, and (4) elaborative ideas emerge in human brains, includes problem definition, data, figures, and information collection, selecting the best solution among several of them, and from this point creating improved or newly discovered products and services.

Organizations need management expertise and practices, motivation, knowledge, mental acuity, techniques, procedures, people with flexibility and imagination to approach issues, and internal access to the organization related to the elements external (e.g., threats to leave the job or income) and internal to achieve and maintain creativity (such as job satisfaction, employee development).

At this point, employee motivation practices include:

A sign of entrepreneurship studies and the social and psychological skills, knowledge, and competencies of entrepreneurs is the ability of employees and

*A Worldwide Regression Analysis of Relations between Creativity, Innovation, and Quality… DOI: http://dx.doi.org/10.5772/intechopen.111744*

businesspeople to use creativity to realize products and services with improved and new features. This is accomplished using processes of continuity, brainstorming, conceptions, support, and confidence [9].

According to some authors [10–12], creativity and knowledge creation are essential for successful organizations. These authors also emphasize how communication, infrastructure, technology, and training all play important roles in this process.

Parallel to this, the idea of the "creative class, an important driver of the economies of the modern era," in conjunction with the "3 T regions" (Technology development, talent empowerment, and tolerance for differences), leads to a high concentration of creativity among professionals who strive to have a higher position of economic development [13].

#### **2.4 Innovation**

According to an OECD report [14] and numerous authors [15–19], business is an innovative process that involves human, financial, and material resources as well as the capacity to produce, using skills, knowledge, and managerial and entrepreneurial competences that are developed during a long and important creative process, although at the beginning, the process can be when subjects submit their goods and services to the market, innovation appears to be a process of the practical implementation of ideas brought by the market, and when these subjects work diligently and consistently to enhance their goods and services. Innovation is defined as "an improvement or something new that presents and brings back value" by the ISO 56000:2020 Standard [20].

Improvement, invention, and dissemination—three components of innovation are shared by all authors who have looked at various facets of this topic [21]. While innovation cannot be viewed as only an invention [22] or as if every innovation is an invention in and of itself [23], not all innovations necessitate dealing with the invention [24].

The creation, distribution, and application of skills, knowledge, and competencies within a system can be positively impacted by laws, procedures, and processes, but excessive bureaucracy and a plethora of restrictions are detrimental to innovation [25].

There are three stages to the innovation process: idea generation and idea empowerment, problem resolution and decision-making, and implementation [26].

The primary drivers of innovation are significant system failures, chance, and earnest efforts made by numerous economic agents. Along with this, there are the movements and demographic shifts, the shift in people's attitudes toward innovation and other topics, and the degree of knowledge, skills, and current scientific capabilities, which are important sources of innovation [27].

The tools and techniques used for problem-solving and decision-making, activities that include agents of many and different economics, and this constitutes a very important aspect regarding the outcomes of public and private entities, which are all included in this aspect and are therefore essential to the success, efficiency, and effectiveness of innovations.

The innovative aspects of products and services are brought to the attention of consumers by combining marketing with its components (advertising, publicity,

public relations, and promotion), a process that involves communication, a process that includes the generation of ideas, the work of individual and group intellectuals, and so on, and mostly this mental and intellectual work, innovative technological changes rather than any activity that is necessarily and primarily related to the use of fixed factors of production, land, labor, and capital [28].

The connections between management, leadership, entrepreneurship, inspiration, and creativity have been studied by several authors [29–32].

According to certain writers, the Triple Helix model [33] serves as an infrastructure for innovation, which fosters interaction and the development of the knowledge economy [25, 34]. They contend that those engaged in science and academia are those who produce and disseminate knowledge. These are the facts that the market's economic agents gather and apply [33]. The company generates and offers funding and opportunities for the development of skills, knowledge, and competencies to support innovation, and the government creates and provides incentives to promote and foster innovation [25].

Every incident involving such things as pandemics and natural calamities fosters standard-setting, innovation, and creativity. The growing interest in innovation has been observed during the Covid-19 pandemic period in the areas and industries of public health, education, distant labor, electronic commerce, and so on [35].

#### **2.5 Concepts of quality and quality culture**

Quality, which is ultimately connected to consumers' expectations for the features of goods and services, demonstrates that it is also connected to customers' perceptions, which are conditioned and subjective. Since meeting customer demands at a particular level is essentially what customers desire, quality is defined by ISO standards as doing so.

It was Edward Deming who first suggested that cost-cutting must accompany productivity development to enhance quality. This approach to quality improvement calls for the use of administrative functions, proper processes, and procedures, as well as design and testing methodologies. Quality is what buyers search for in goods and services, according to Peter Drucker. Consumers are always willing to pay more for quality than for the money that producers wish to receive. This leads to the perspective that the essence of quality and quality culture is being able to satisfy consumer requests.

The relationship between quality, quality management, and quality culture and the organization's management, in general, has to do with the strategy of placing the customer at the heart of the business and attending to their demands—a long-term dedication to the client, collaboration, the kaizen approach (constant improvement), ongoing training for employees during their tenure with the organization, setting up the right conditions for the fulfillment of freedom of action through control, empowerment, and involvement of employees, and so on. This quality system encompasses factors such as employees, workplace health and safety, the manufacturing process, organizational finances, information creation and management, research and development, procurement practices [2, 36].

The relationship between management principles and ISO 9001 is depicted in the image below (**Figure 1**):

*A Worldwide Regression Analysis of Relations between Creativity, Innovation, and Quality… DOI: http://dx.doi.org/10.5772/intechopen.111744*

**Figure 1.**

*The management principles and ISO 9001 relations [37].*

The values necessary to realistically implement continuous improvement are related to quality. For this, several factors are required, through which it is possible to develop the organizational philosophy, the workgroup culture, the mobilization and motivation of people involved in creative and innovative projects, and so on. Many scholars in the field of quality management characterize this as a social conflict that keeps the organization's members united [38].

In the jargon of quality management, this is exactly what subject culture means; it is what ties individuals in an organization together and connects them to the values they support and develop, with how these people naturally use organizational structures, controls, and mechanisms, and so on [39]. This culture encourages you to strive for excellence and creates a setting where everyone in the company is committed to raising quality. Now, each employee sees himself as a customer, a supplier, and an employee. It's a great creative idea to strive to complete everything as well as you can right away.

First, from this perspective, it should be made clear that it is not claimed that since there is room for improvement, there is no reason to do everything well from the start, as this mentality increases costs for the organization. Instead, the approach aims to evaluate every step of the creation of products and services in every organization where a quality culture exists and is functional, as this prevents the passing of time [40].

Thus, the improvement of both individuals and organizations along the path of continuous realization of goods and services, the development of a climate of respect and tolerance among employees, and the development of entrepreneurial skills, knowledge, and competencies are all closely related to quality, its management, and quality culture (4). The capabilities of the organization and proof that these capabilities are regarded and used properly.

The domains that are known and valued by every individual who comprises the organization and who identifies themselves with these domains are what constitute the quality culture, which is manifested in the quality of products and services [41].

The main principles of "achieving goals through training" and "bringing benefits through value and opportunities" [42], which aim for excellence, recognition, and application of best practices and experiences to achieve and maintain standards, are precisely these approaches to quality and quality culture that set Europe apart. This is a managerial strategy that makes it possible for the beliefs, values, and principles of the people who make up the organization and all other interested parties to create and use the culture of this organization. Goals, strategies, and operational objectives are clearly defined, and individuals are responsible for predetermined and defined processes and procedures.

In this regard, many studies have recently been conducted on quality, quality management, quality culture, and their significance for attaining and maintaining competitive advantages, corporations'social responsibility, sustainability, and organizational continuity, as well as the ethics of business activity and raising standards of living, among other topics [2, 39, 43, 44].


**Energy Efficiency in Cooperative Wireless Sensor Networks**

Glauber Brante, Marcos Tomio Kakitani and Richard Demo Souza

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/47780

## **1. Introduction**

20 Will-be-set-by-IN-TECH

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profiling, *Design Automation Conference, 2001. Proceedings*, pp. 220 – 225.

**7. References**

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Wireless Sensor Networks (WSNs) are composed by a large number of sensor nodes, which are usually small in size and are deployed inside or close to some phenomenon of interest. Moreover, since usually there is no need for regular or predefined deployment, the sensors can be placed over irregular or inaccessible areas. Therefore, according to [2], it is expected that the sensors possess self-organizing capabilities. Such attributes provide to the WSNs a large number of applications such as medical, military, and commercial. For instance, in medical applications wireless sensor networks can be used in patient monitoring systems. In the military, the fast set-up and self-organizing characteristics of the sensors make WSNs interesting for communication applications, security, monitoring, and terrain recognition. Commercial applications can include inventory management, product quality control and monitoring disaster areas.

The nodes in a WSN are typically equipped with limited power sources such as batteries, whose recharge or replacement may not always be possible or of economical interest. Moreover, batteries capacity presented a modest increase in the last decades when compared to the gains obtained in computational capacity and wireless throughput, which motivates the study of the energy efficiency of these devices. The wireless throughput has grown by roughly one million times and the computational capacity has had an increase of 40 million times since 1957, while the average nominal battery capacity has increased only 3.5 percent per year over the last two decades, as shown in [11, 24]. Thus, according to [9], due to these power source limitations, the overall energy consumption and energy efficiency have great importance and are major concerns in the design and analysis of wireless sensor networks.

Another challenge faced by WSNs is the wireless environment itself. The wireless channel is a difficult and unpredictable communication medium. A signal transmitted through wireless is subjected to many factors, such as noise, random fluctuations in time (usually referred to as fading), attenuation due to moving objects, etc. Therefore, a reliable system design comes at the expense of a significant amount of power, required to transmit a block of data from

©2012 Brante et al., licensee InTech. This is an open access chapter distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0),which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2012 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

#### 2 Will-be-set-by-IN-TECH 374 Energy Effi ciency – The Innovative Ways for Smart Energy, the Future Towards Modern Utilities Energy Efficiency in Cooperative Wireless Sensor Networks 3

the sensors to the sink. According to [14], one of the most promising techniques to overcome such limitations of the wireless medium is to exploit diversity techniques. Time diversity, frequency diversity and spatial diversity are among the most common strategies used in wireless transmissions. For instance, the use of error correction codes is an example of time diversity, introducing a level of correlation among the symbols to be transmitted. Orthogonal Frequency-Division Multiplexing (OFDM) and spread spectrum techniques are examples of frequency diversity. Recently, spatial diversity, through the use of multiple antennas, has been on the focus of many works, as for instance in [3, 12, 30].

starts with simple examples considering only three nodes, as in the case of the classical relay channel in [31], and is further generalized to multiple nodes randomly distributed over a field.

Energy Effi ciency in Cooperative Wireless Sensor Networks 375

The modern cooperative communications concept is based on the classical relay channel model in [31], which allows different nodes to share resources in order to achieve a more reliable transmission. Relay channel is usually referred to systems where the relay is a dedicated device, without information of its own to transmit. On the other hand, the term cooperative communication is used when the relay is another user or node in the same network, which also has information to transmit. The main objective of this approach is to achieve spatial diversity gains, which usually are obtained by adding more antennas to the nodes. However, in cooperative communications spatial diversity is obtained through the shared use of the source and the relay antennas. Thus, even if each device has only one antenna, spatial diversity can be obtained, what in this case is usually referred to as

The spatial diversity exploits the use of multiple antennas at the transmitter and/or receiver in order to create independent paths for transmitting the same information, allowing the system

• improve the link quality, and therefore decrease the transmission error probability as in

When only the receiver is equipped with multiple antennas, as illustrated in Figure 1(a), diversity combining techniques such as Maximal Ratio Combining (MRC) can be applied. The case that only the transmitter has multiple antennas is illustrated in Figure 1(b). In this scenario, one of the most effective techniques is the Alamouti scheme, which establishes a space-time coding for the symbols to be transmitted. And when there is a combination of multiple antennas at both the transmitter and the receiver the system is known as MIMO

**Figure 1.** Spatial diversity through the use of multiple antennas: (a) at the receiver; (b) at the transmitter;

A comparison of different spatial diversity techniques is shown in Figure 2. The figure compares the bit error rate (BER) as a function of the signal-to-noise ratio (SNR), which is defined as *Eb*/*N*0, where *Eb* is the energy per information bit, and *N*0 is the power spectral density of the noise. In this particular example, the wireless channels are independent and

• increase the transmission rate without increasing the bandwidth, as in [12, 33];

• combine the two previous alternatives in a hybrid option, as in [13, 39].

(Multiple-Input Multiple-Output), as shown in Figure 1(c).

Then, Section 4 presents the final comments of this chapter.

**2. Cooperative communications**

cooperative diversity.

**2.1. Spatial diversity**

(c) at both (MIMO system).

to:

[3, 30];

However, for the spatial diversity gains to be obtained in practice it is necessary that the antennas are sufficiently spaced at the transmitter and receiver. Small-sized devices such as sensor nodes do not dispose of sufficient area to place multiple antennas appropriately spaced. Another practical way to obtain spatial diversity is through the use of cooperative communications. Cooperative communications are based on the channel model introduced by [31], which was originally composed by three nodes: one source of information, the destination of the communication, and a relay node. The relay node is responsible for helping the communication between the source and the destination, so that it may be possible to establish a more reliable communication, or to reduce the transmission power. Thus, exploiting the broadcast nature of the wireless channel, the relay may be able to overhear the transmission from the source in a first time instant, and then retransmit this information to the destination in a second time instant.

At the time that it was proposed by Van der Meulen in 1971, the relay channel was of more theoretical interest. However, due to technological advances of wireless communications in the last decades, a renewed interest in cooperative communications appeared motivated by the recent works of [20, 26], showing that cooperation is a strong practical candidate to improve robustness and help in reducing the energy consumption of wireless networks.

Motivated by these recent advances in the cooperative communications field, and by the importance of reducing the energy consumption of wireless devices, the energy efficiency of some transmission schemes for wireless sensor networks is analyzed in this chapter. The goal is to outline the best strategy in terms of energy efficiency given the characteristics of a network. Such characteristics can include, for instance, the amount of error allowed at the receiver, or the maximum delay in the communication between two nodes. Moreover, in order to approximate the theoretical results to a practical sensors network scenario, the following analysis seeks to model the network in a realistic way. As the nodes in a WSN are often at close distances to each other, the severity of the wireless fading must be taken into account, since when nodes are closer, a better wireless channel is expected. Moreover, another factor that cannot be ignored in the energy efficiency analysis of WSNs is the consumption of the internal circuitry of the devices. As shown in [10, 25, 28], in networks where the nodes are distant, the transmit power dominates over the consumption of the RF circuits. However, when the nodes are closer, the circuitry consumption becomes relevant.

In the following, Section 2 reviews some important concepts of cooperative communications. This section starts by showing the gains that can be obtained with spatial diversity, followed by the introduction of the relay channel as a practical way to obtain spatial diversity. Moreover, some cooperative protocols are presented at the end of the section. In the sequence, Section 3 shows some applications of such concepts to wireless sensor networks. Various WSN scenarios are analyzed in terms of the energy consumption of the devices. The section starts with simple examples considering only three nodes, as in the case of the classical relay channel in [31], and is further generalized to multiple nodes randomly distributed over a field. Then, Section 4 presents the final comments of this chapter.


impairment do develop mental representations of their attachment figures, but that these representations start at a later age and/or show different characteristics than in sighted peers. This delay may affect their emotional functioning. Furthermore, infants with visual impairments need more help and encouragement to become aware of their range of motion. This help prevents them from remaining in their natural passive state, which could hinder their physical development, including posture and mobility [35], and affect their exploration and social and emotional development.

Next to the influence of a hearing or visual impairment, a child's physical development may also impact their emotional development. Persons with an intellectual disability have an increased risk for physical disabilities and epilepsy [19,36]. Vandesande et al. [37] conducted a study among children with severe and profound intellectual disabilities during a stressful situation, where the child's parents and a stranger were present. Interestingly, the child's differentiated responses to comfort seemed to be related to their fine motor skills [37]. Therefore, to adequately support persons with intellectual and physical disabilities, it is important to examine the effects of the disabilities on the different domains of emotional development.

According to Došen [38], the social–emotional development of a neurotypical child goes through several stages, and these stages are linked to social–emotional developmental milestones [38–40]. For children with intellectual disabilities and sensory, physical, or multiple impairments, reaching these milestones requires more effort than it does for children without these impairments. Up to now, to our knowledge, no studies have been conducted among adults with intellectual disability to examine the effect of visual, hearing, or physical impairments on emotional functioning. Therefore, the aim of this study was to examine whether physical or sensory impairments of adults with intellectual disabilities can predict their level of social–emotional functioning.

#### **2. Materials and Methods**

#### *2.1. Setting and Design*

The study was conducted from May 2016 to November 2020 in three hospitals and five home care facility centers in Belgium, the Netherlands, and Germany. Inclusion criteria were age >18 years and a diagnosis of intellectual disability. There were no exclusion criteria within this respective population. A sample of 724 adults with intellectual disabilities was recruited, among which 246 persons (34%) had an additional physical disorder and/or sensory impairment such as a hearing and/or visual impairment, movement disorder, and/or epilepsy.

The participating organizations were Tordale in Torhout (Belgium), Cordaan in Amsterdam (Netherlands), ORO in Helmond (Netherlands), De Twentse Zorgcentra in Losser (Netherlands), Bartiméus in Doorn (Netherlands), the Evangelisches Krankenhaus Königin Elisabeth Herzberge in Berlin (Germany), Klinikum München Oberbayern in München (Germany), and St. Lukas-Klink in Liebenau (Germany). The persons themselves or their legal guardians gave their informed consent for participation in this study.

#### *2.2. Participants*

The total study sample consisted of 724 participants with intellectual disabilities. Due to missing information about the researched impairments, two persons were omitted from the analyses, leaving a total sample of 722 participants. The average participant age was 37.4 years (18–76 years, *SD* = 13.3) and males were slightly in the majority (56.4%). The degree of intellectual disability ranged from mild (IQ 50–55 to 70: 28.2%), moderate (IQ 35–40 to 50–55: 37.4%), and severe (IQ 20–25 to 35–40: 26.8%), to profound (IQ < 20–25: 7.6%).

The age of the 246 (34%) participants with sensory impairments ranged from 18 to 76 years, and the average age was 39.9 years (*SD* = 13.7). This sample included more males (60.2%) than females. All levels of intellectual disability were represented; most of the participants had moderate intellectual disabilities (38.2%), followed by severe intellectual disabilities (28.5%), mild intellectual disabilities (19.5%), and profound intellectual disabilities (13.8%). In this group with sensory impairments, 44 persons (17.9%) had hearing impairments and 64 persons (26%) had visual impairments. In the sample with sensory impairments, 87 persons (35.4%) had a movement disorder. Epilepsy was reported in 130 persons (52.8%).

#### *2.3. Assessment*

The level of emotional development (ED) was assessed using the SED-S [10]. The SED-S is a semi-structured interview consisting of 200 binary items in eight domains, concerning different aspects of daily life behaviors. The scale assesses five developmental stages with reference ages ranging from 0 to 12 years of age. Each level of ED is assessed by five items per domain. The eight domains are: (1) *Body* (Relating to His/Her Own Body), (2) *Others* (Relating to Significant Others), (3) *Object* (Dealing with *Change*: Object Permanence), (4) *Emotions* (Differentiating Emotions), (5) *Peers* (Relating to Peers), (6) *Material* (Engaging with the Material World), (7) *Communication* (Communicating with Others), and (8) *Affect* (Regulating Affect).

Within the SED-S items, behaviors for a certain level of ED are described, which are either typical in the respective person ("yes" answers) or not typical ("no" answers). To determine the level of ED in a certain domain, the number of "yes "answers is counted. The level with the most "yes "answers is the domain-wise level of ED. Estimating the overall level of ED, these domain-specific results are ordered from low to high, and the four lowest domains determine the overall result. Trained psychologists, psychiatrists, developmental psychologists, or ortho-pedagogues conducted the interview with two to five informants, such as family members or close caregivers. The assessment relied on behaviors displayed during the previous 2 weeks.

Expert validity can be taken as given, as the scale is based on a survey of developmental psychology experts and their assessments of behaviors typical for specific levels of development, [10]. Validation against a group of 160 typically developed children showed a high degree of correspondence (81% exact agreement; 0.95 weighted kappa value) [11]. An exploratory factor analysis provided a one-factor model with a good model fit in 724 adults with ID, most of them having additional mental health problems [15,41], in 118 children with ID and mental health problems [9] and in 83 healthy adults with ID [14,41]. Divergent validity was found for chronological age in children with ID [9] and in healthy adults with ID [14,41]. Convergent validity with the Vineland Adaptive Behavior Scale could be seen in the children's sample (r = 0.642, *p* < 0.001; [9]). Strong negative associations with the severity of ID could be shown in 327 adults with ID and mental health problems (r = −0.654, *p* < 0.001; [11]), in 83 adults with ID without mental health problems (−0.753, *p* < 0.001; [14,41]) and in 118 children with ID (G = −0.69; *p* < 0.001; [9]). Inter-rater reliability for 25 typically developed children was 1.0 (Cohen's kappa). Internal consistency as measured by Cronbach's alpha was 0.99 in typically developing children [11], 0.94 in 118 children with ID [9] and 0.92 in 83 adults with ID without mental health problems [14,41].

The degree of intellectual disability was diagnosed using the Disability Assessment Schedule (DAS), which is an informant-based structured interview [41]. It poses several questions about adaptive behaviors in four parts: continence, self-help skills, communication, and (cognitive) skills. Depending on the presence of these behaviors, points are given and summed to a total score (minimum 15 points; maximum 71). The total score corresponds with the levels of ID (mild, moderate, severe, profound). The DAS is a reliable measure when applied by trained professionals [42]. Evidence pertaining to its validity in people with ID is provided by correlation analysis with the Colored Progressive Matrices and the Columbia Mental Maturity Scale [43].

The data regarding hearing and visual impairment, movement disorders, and epilepsy were systematically recorded upon the assessment of the SED-S.

#### *2.4. Statistical Analysis*

The statistical analyses were conducted using IBM SPSS 27 Statistics for Windows, USA. Associations of hearing and/or visual impairment, and movement disorder and/or epilepsy, with the severity of the intellectual disability and the level of ED (overall and domain wise) were examined by applying an ordinal logistic regression analysis. The ordinal logistic regression model was chosen because of the dichotomous variable structure of the impairments and because the severity of the intellectual disability and level of ED were ordinal variables [44]. A further key assumption of ordinal logistic regression analysis is that of assumption of proportional odds, which in SPSS is examined with the test of parallel lines. Chi-square was used to determine whether the assumed model with an explanatory variable was improved in comparison with the baseline model without this explanatory variable.

A significant *p*-value indicates an improved fit to the data. Nagelkerke *R*2 is reported as a pseudo *R*2 value, indicating the proportion of variation in the outcome that can be accounted for by the explanatory variables. To specifically analyze the relationship between the sensory impairments and the intellectual disability and ED, odds ratios and the Wald χ2 were calculated to investigate whether a significant impact of the explanatory variables existed.

#### **3. Results**

Assumptions of parallel lines were met for all our analyses (*p* > 0.05) with one exception: for the regression of the domain *Others* on the four impairments, it was significant with *p* = 0.044, meaning these results should be interpreted cautiously.

#### *3.1. Number of Impairments as a Predictor of Intellectual Disability and ED*

Since many participants had more than one reported impairment, the number of impairments (e.g., visual, hearing) was analyzed as a predictor of the intellectual disability and ED. For intellectual disability, ordinal regression analysis revealed that higher numbers of co-occurrent physical impairments were related to more severe intellectual disability (Δχ2 = 37,85, *df* = 4, *p* < 0.001; Nagelkerke *R*2 = 0.055). The individual odds ratios were nonsignificant. Additionally, the level of ED improved the model fit of the regression analysis when the number of impairments was used as a predictor to explain the level of ED (Δχ2 = 11.56, *df* = 4, *p* < 0.021; Nagelkerke *R*2 = 0.017). Again, the individual odds ratios were nonsignificant.

#### *3.2. Different Forms of Impairments as Predictors of Intellectual Disability and ED*

Looking at the frequency of the different levels of intellectual disability and ED for the different groups of impairments (reported in Tables 1 and 2), not only the presence or absence of physical or sensory impairments, but also the type of impairment was relevant. For an overview of the results, see Table 3.

**Table 1.** The Different Impairments and Severities of Intellectual Disability.

Note. In parentheses are percentages per column. Regression analyses for the impairments marked with \* showed a significant association with the severity of intellectual disability.

**Table 2.** The Different Impairments and Levels of Emotional Development.

Note. In parentheses are percentages per column. Regression analyses for the impairments marked with \* showed a significant association with level of ED.

**Table 3.** The associations between sensory impairments, ID, and ED.

Hearing impairment. Hearing impairments were not associated with the severity of intellectual disability or the level of ED in any of the ten analyses (Details for the nonsignificant analyses are available from the authors upon request).

Visual impairment. Having a visual impairment was related neither to the intellectual disability nor to the level of overall ED. However, visual impairments significantly predicted lower levels of ED on the domains of *Body* (odds ratio 1.65, 95% CI 1.022–2.68; Wald *χ*2(1) = 4.082, *p* = 0.043) and *Material* (odds ratio 1.71, 95% CI 1.06–2.72, *Wald χ*2(1) = 4.823, *p* = 0.028).

Movement disorder. A movement disorder was related to more severe forms of the intellectual disability (odds ratio 0.28, 95% CI 0.18–0.43; Wald *χ*2(1) = 33.446, *p* < 0.001). Furthermore, the presence of a movement disorder was related to lower levels of ED in general (odds ratio 1.59, 95% CI 1.05–2.42; Wald *χ*2(1) = 4.815, *p* = 0.028) and for the domains of *Body* (odds ratio 2.25, 95% CI 1.47–3.45; Wald *χ*2(1) =13.988, *p* < 0.001), *Others* (odds ratio 1.66, *95% CI* 1.06–2.72; Wald *χ*2(1) = 5.591, *p* = 0.018), *Material* (odds ratio 1.66, 95% CI 1.10–2.50; Wald *χ*2(1) = 5.821, *p* = 0.016), and *Communication* (odds ratio 2.14, 95% CI 1.41–3.24; Wald *χ*2(1) = 12.964, *p* < 0.001).

Epilepsy. Epilepsy was associated with more severe forms of intellectual disability (odds ratio 0.65, 95% CI 0.46–0.93; Wald *χ*2(1) = 5.590, *p* = 0.018), but not with the level of ED (neither overall nor domain wise).

#### **4. Discussion**

The aim of this study was to examine if adults with intellectual disability and physical and/or sensory impairments score lower on the SED-S than adults with intellectual disability but without these additional impairments. At first, the results indicated that an accumulation of impairments predicts lower emotional functioning. This could be explained by one impairment significantly affecting the other. For example, as Fraiberg [35] reported, a visual impairment may influence physical development. This in turn may shape emotional development. What is more, persons with a disability are unable to compensate

for the co-occurrent impairment. For instance, Gunther [45] reported that the presence of a visual impairment in addition to an intellectual disability means that vision cannot be used to compensate for the intellectual disability, and vice versa. Therefore, people with visual and intellectual disabilities find it is even more difficult to understand social relationships than do people with only intellectual disabilities [46]. Additionally, as found in this study, in persons with a visual and intellectual disability as well as an added hearing impairment, emotional functioning is significantly lower than it is in adults with intellectual disabilities with either a hearing or a visual impairment (not having both impairments).

A second finding of this study is that hearing impairments seem not to be associated with intellectual disability or emotional development. These findings indicate that although there is a risk for social–emotional difficulties in children [30], the focus on learning to communicate [29] and socially interact may eventually buffer the effect of the hearing impairment on emotional functioning. Early intervention programs focusing on joint engagement and emotional availability can be used for this purpose [47,48].

Third, in this study, no significant effects of visual impairment and intellectual disability on the total score for emotional development were found. However, it is important to note that there were domain-specific outcomes, namely in the domains *Relating to His/Her Own Body* and *Engaging with the Material World*. Zooming in on the items of these domains, the hindering effect of the visual impairment becomes more clear: for example, in the use of tactile senses to explore the world, the need to feel safe in an open space, and requiring more time to explore materials, while contact with others is less evident. This may confirm what Fraiberg [33] suggested, namely that emotional development could be delayed and/or show different characteristics than it does in sighted peers. These outcomes are presumably of great importance for (early) intervention programs, which it seems should be more focused on these aspects of socio-emotional development. Additionally, as for all persons, disharmonious emotional development may affect well-being, and therefore should be noticed [49].

A fourth finding of this study is that having a physical disability was associated with more severe forms of intellectual disability and lower levels of emotional functioning. These results indicate that a tailored approach is needed for these persons. Due to the severe or profound disability, repetition, patience, and interaction are needed for emotional development. Nowadays, technology can also be used in daily care to support emotional development [50] and communication. The results of this study stress the importance of addressing these caregiving and assistive technology needs in interventions.

Fifth, epilepsy was related to intellectual disability but could not be linked to emotional development. Thus, epilepsy does not seem to directly obstruct emotional functioning, although adequate care and support for emotional and physical needs is required.

Sterkenburg et al. [9] found a significant relation between visual and hearing senses and emotional development in children. However, in this study the focus was on adults with a mean age of 37.4 years and less-significant links were found. Matching the findings reported by Fraiberg [33] for children with a visual impairment, there was a delay in development, but there seems to be a catching up later in life. However, accumulated impairments did show significant relations with emotional development. Thus, (early) intervention programs are essential and should consider the different co-occurring impairments. There are programs such as: "Development of an attachment relationship" [51]; "Learning together" [52]; "Little room" [53]; "Barti-mat" [54], and the Light Curtain [55]. These results may encourage the application of early interventional strategies that impact both physical and social–emotional skills in people with intellectual and additional disabilities. Hereby, longer-term outcomes, quality of life, and social participation may be improved substantially. Therefore, we recommend continued investment in and provision of (early) intervention programs for parents of infants with intellectual disability and sensory impairment. Additionally, there is a need for more projects focusing on parent–child interaction and the use of technology in supporting the social and emotional development of persons with intellectual disability and sensory impairment.

#### *Limitations*

During the assessment, the data regarding visual and hearing impairments, physical disabilities, and epilepsy were reported based on participants' records. However, on-the-spot assessments were not conducted. Thus, the data may be incomplete or not adequately reported in the records and may, therefore, be biased. However, comparing the prevalence of the impairments reported in this study to the prevalence mentioned in the literature [20–23], this does not seem to be the case.

The reported results are based on cross-sectional data, so causal interpretations need to be made with caution. A longitudinal study that follows the development of children with and without intellectual disabilities and physical impairments would be required to be able to fully understand how these factors influence each other and social–emotional development.

The study was conducted in three Western European countries. Due to the small sample size for each of the studied impairments, comparisons between countries were not possible. There may be differences that we cannot now report and that need to be studied in future research. Furthermore, the (early) interventional care in the studied countries may explain the possible catching up when people have reached adulthood; such catching up may not occur in other parts of the world. Replication of this study is therefore needed, covering a broader spectrum of the world population.

#### **5. Conclusions**

In summary, higher numbers of co-occurrent physical and/or sensory impairments were related to more severe intellectual disability and lower levels of emotional development (ED). Interestingly, movement disorders affected intellectual and ED, while auditory impairment did not affect ED. Epilepsy correlated only with the degree of intellectual disability but not with the level of ED. On the domain level, *Relating to His/Her Own Body* and *Engaging with the Material World* showed associations with visual impairments and movement disorder, the latter disorder also predicting lower levels of ED in the domains *Relating to Significant Others* and *Communicating with Others.* Considering these overall and specific effects of different impairments on the intellectual and emotional functioning of people with multiple disabilities may align early interventions and thereby further improve long-term outcomes.

**Author Contributions:** M.I. and M.F. conducted the analyses, P.S.S. wrote the introduction and discussion, and T.S. finalized the paper and coordinated the study. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was supported by funds of the v. Bodelschwinghsche Stiftungen Bethel (c.f. Board Meeting Protocol from 19.1.2016). PSS was funded by the Bartiméus Fund (reference number P00238).

**Institutional Review Board Statement:** The study was conducted according to the ethical principles of the 1975 Declaration of Helsinki. All organizations acquired ethical approval separately. For Belgium, the University of Ghent ethics commission of the Faculty of Psychology and Pedagogic Science gave their permission. The ethics board in each Dutch organization gave approval. For Germany, the Charité University Hospital in Berlin (Ethics vote: EA2/193/16) gave their permission; additionally, every hospital received ethical approval from its own ethics commission.

**Informed Consent Statement:** Informed consent was obtained from all subjects involved in the study.

**Data Availability Statement:** On request.

**Acknowledgments:** We thank all the participants, their parents or relatives, and the caregivers who contributed to this study. We thank the caregiving organizations for facilitating the study. Thanks also to Paula Verbon-Dekkers for providing feedback on the manuscript. Great appreciation goes all the members of the Network of Europeans on Emotional Development (NEED) who participated in the data collection.

**Conflicts of Interest:** T.S. receives royalties from different publishers (esp. Hogrefe, Kohlhammer) for various books and scales and funds of the v. Bodelschwinghsche Stiftungen Bethel.

#### **References**

## *Article* **Intellectual Disability Profiles, Quality of Life and Maladaptive Behavior in Deaf Adults: An Exploratory Study**

**Johanna Eisinger 1, Magdalena Dall 1,\*, Jason Fogler 1,2,3, Daniel Holzinger 1,4,5 and Johannes Fellinger 1,4,6**

	- Medical University of Vienna, 1090 Vienna, Austria

**Abstract:** Individuals who are prelingually deaf and have intellectual disabilities experience great challenges in their language, cognitive and social development, leading to heterogeneous profiles of intellectual and adaptive functioning. The present study describes these profiles, paying particular attention to domain discrepancies, and explores their associations with quality of life and maladaptive behavior. Twenty-nine adults with prelingual deafness (31% female) and mild intellectual functioning deficits (mean IQ = 67.3, SD = 6.5) were administered the Vineland Adaptive Behavior Scales-II (VABS-II) and an adapted sign language version of a quality of life scale (EUROHIS-QOL 8). Intellectual disability domain discrepancies were characterized as at least one standard deviation difference between the social domain and IQ and the practical domain and IQ, and a significant difference, according to the VABS-II manual, between the social and practical domains. Domain discrepancies were found between intellectual functioning and both the practical (58.6%) and social domain (65.5%). A discrepancy between intellectual and social functioning was significantly associated with a higher level of internalizing maladaptive behavior (T = 1.89, *p* < 0.05). The heterogeneous profiles highlight the importance of comprehensive assessments for adequate service provision.

**Keywords:** intellectual disability; deaf; adaptive behavior; intellectual functioning; domain discrepancy; maladaptive behavior; quality of life

#### **1. Introduction**

Deafness is a heterogeneous condition that can impact communication, social–emotional development and cognitive development [1]. Around 7 per 10,000 people have severe to profound hearing loss, with onset before language acquisition [2,3].

Approximately one-third to one-half of individuals who are prelingually deaf or hard of hearing have additional disabilities [4,5], most commonly intellectual disability [6]. Additive deprivation of language and communication, stemming from delayed identification, insufficient or late provision of hearing technology and little or no access to sign language, further impedes these individuals' community participation [7–10].

The diagnostic criteria for intellectual disability have been revised in the Diagnostic and Statistical Manual of Mental Disorder-Fifth edition (DSM-5; [11]) to encourage a more comprehensive patient assessment, with greater weight given to adaptive functioning than intellectual functioning for the purpose of ascribing intellectual disability severity [11]. Whereas intellectual functioning generally involves abilities such as reasoning, problem solving, knowledge and experience [12], adaptive functioning refers to the skills that are

**Citation:** Eisinger, J.; Dall, M.; Fogler, J.; Holzinger, D.; Fellinger, J. Intellectual Disability Profiles, Quality of Life and Maladaptive Behavior in Deaf Adults: An Exploratory Study. *Int. J. Environ. Res. Public Health* **2022**, *19*, 9919. https:// doi.org/10.3390/ijerph19169919

Academic Editor: Shoumitro Deb

Received: 14 July 2022 Accepted: 7 August 2022 Published: 11 August 2022

**Publisher's Note:** MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations.

**Copyright:** © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).

learned and performed to meet the everyday demands of one's community or society [13], suggesting that adaptive behavior may be the more malleable (and hence important) intervention target to unlock an individual's full potential. Adaptive functioning includes three domains: the conceptual domain, including applied skills in language, reading, writing, math, reasoning, knowledge and memory; the social domain, referring to empathy, social judgment, interpersonal communication skills and the ability to make and retain friendships; and the practical domain, including self-management in areas such as personal care, job responsibilities, money management, recreation and organizing school and work tasks [11].

Intellectual and adaptive functioning, the two aspects of intellectual disability, are related but separate constructs [13]: a large meta-analysis of 148 samples containing a total of 16,468 participants showed a moderate relationship (r = 0.51) between intelligence and adaptive behavior, which is stronger in lower IQ groups [14].

With this more nuanced definition of adaptive functioning has come greater interest in intellectual disability domain discrepancy, in which one domain is markedly more deficient than another, as well as inquiry into whether different populations have unique, or at least specific, intellectual disability profiles. Sparrow, Cicchetti and Balla [15], authors of the Vineland Adaptive Behavior Scales-II (VABS-II), provide various adaptive functioning profiles based on pairwise comparison of the four adaptive behavior domains (communication, socialization, daily living skills and motor skills) outlined in the Vineland-II manual. When comparing the specific profile of individuals with hearing impairment with samples matched by age range and controlled for sex, ethnicity and education level, the researchers found that individuals with hearing impairment had lower levels of communication and daily living skills than the IQ-matched sample with typical hearing. The socialization scale appeared as a relative strength, though still lower than the non-clinical group [15].

There is a growing body of research on adaptive profiles in individuals with different neurodevelopmental disorders [16–22]. Tillmann et al. [23] examined how IQ and levels of ASD symptom and autistic trait severity are associated with adaptive functioning and suggested that core ASD-related social communication problems contribute both to adaptive functioning impairments and to the discrepancy between IQ and adaptive functioning. Further supporting this point, a discrepancy between intellectual functioning and adaptive skills was found to be significantly correlated with depression and anxiety in a sample of adults with ASD without intellectual disability, in which socialization was by far the largest weakness [24].

Studies correlating adaptive profiles with such clinically relevant variables as quality of life (QOL) and problem behavior (e.g., [13,25]) show divergent results. Tassé [13] and Simoes et al. [26] found a positive correlation between adaptive behavior and QOL in samples of individuals with mild-to-moderate intellectual disability, whereas Graves et al. [18] did not find significant associations between adaptive functioning and self-reported QOL in a sample of adults with Down syndrome. Jones et al. [27] found higher levels of problem behavior to be associated with more severe degrees of intellectual disability. Curiously, Balboni et al. [25] found that a subgroup of individuals with intellectual disability with the highest levels of problem behavior also had higher levels of adaptive behavior, explaining that a basal level of adaptive skills appears to be necessary for the person to be able to engage in their environment, positively or negatively.

No research to date has investigated the intellectual disability profiles and the relationships between intellectual disability domain discrepancies, QOL and maladaptive behavior in a population with prelingual deafness and intellectual functioning deficits. Hence, the main aim of this study is twofold: (a) to describe the intellectual disability profiles and potential intellectual disability domain discrepancies in a sample of adults who are deaf with borderline and mild cognitive functioning impairment and (b) to explore how these intellectual disability profiles and domain discrepancies are related to maladaptive behavior and self-reported QOL in this population. We explored whether expressed intellectual disability domain discrepancies between cognitive potential and lower social and practical

abilities are experienced as stressful barriers to unlock one's potential and therefore may be linked with lower quality of life and increased rates of maladaptive behavior.

#### **2. Materials and Methods**

#### *2.1. Participants*

This cross-sectional exploratory study was conducted within three therapeutic living communities (Lebenswelt) specifically developed to accommodate the needs of individuals with deafness and additional disabilities, focusing on supporting communication, social relationships, conflict resolution and work satisfaction. They are characterized by the constant use of sign language; one-quarter of the staff members are deaf themselves [7].

We recruited 29 individuals (9 women and 20 men) who met the inclusion criteria of having at least moderate hearing impairment and an IQ score between 50 and 85 (see Table 1). Of these participants, 93% were profoundly deaf and 7% had moderate hearing loss. Nearly all the participants joined their therapeutic communities with lifetime histories of potentially traumatic events—a sadly common finding among members of the deaf community [28,29]—and about 38% had experienced at least one depressive episode [30]; however, no participant was experiencing an active depressive episode during the time of data collection. Their length of enrollment in the therapeutic living communities ranged from 6 months to 20 years. Most of the participants (n = 23; 79.3%) lived and worked in these communities, and the remaining participants (n = 6; 20.7%) only took part in the workshop facilities. Their mean age was 46.89 years (SD = 16.42, range 20–73 years), and their mean IQ score was 67.31 (SD = 6.49, range 57–82). Based on the ICD-10/WHO criteria, the majority (72.4%) were classified as having mild deficits indicated by an IQ score between 50 and 69 [31]. In addition, half (51.7%) of the participants were currently diagnosed with intellectual disability with challenging behavior (F70.1 (ICD-10)), 20.7% with cerebral palsy, 13.8% with epilepsy and 13.8% with autism. Table 1 displays the sample characteristics in detail.

**Table 1.** Sample characteristics.

This study was approved by the ethical committee of the hospital St. John of God in Linz, Austria. Consent was given by the participants themselves and/or by their legal guardians (if applicable).

#### *2.2. Instruments*

2.2.1. Intellectual and Adaptive Functioning

The Vineland Adaptive Behavior Scales-II [15] is a comprehensive measure of adaptive behavior. This standardized norm-referenced assessment instrument provides information on an individual's adaptive behavior from birth to 90 years of age across motor, communication, daily living and socialization skills. A standard score (M = 100, SD = 15) for each domain is calculated as well as a summary adaptive behavior composite score. The subscales of the Vineland-II do not perfectly align with the current tripartite model of adaptive behavior described in the DSM-5 s definition of intellectual disability. Tassé and Mehling [12] proposed the following alignment or "cross-walking" of the VABS-II domains with the three domains of adaptive functioning identified in DSM-5: communication = conceptual skills; socialization = social skills; and daily living skills = practical skills. Accordingly, the socialization and daily living skills subscales of the Vineland-II were used to address the social and practical domains. However, two of the three sections of the communication subscale relate to the comprehension and production of spoken language. After adapting comprehension items to a visual modality, many items specifically referring to the structure of spoken language (e.g., intonation, verb inflection, prepositions, pronunciation, pronouns) had to be replaced by Austrian sign language items estimated to be functionally equivalent and of a comparable level of complexity. This non-validated adaptation resulted in significant floor effects that strongly weighed against its being considered for measuring the conceptual domain in this group of adults who are deaf with intellectual disability (see Figure 1).

**Figure 1.** Boxplots of the domains of intellectual disability (standard scores of Vineland-II domains and SON-R 6-40).

To assess participants' intellectual functioning, we administered the Snijders-Oomen Non-verbal Intelligence Scale for individuals (SON-R 6-40; [32]). The SON-R 6-40 assesses the participant's non-verbal cognitive developmental level and provides a standard IQ score (M = 100, SD = 15), making it relatively easy to compare with the standard scores derived from the two VABS-II subscales.

#### 2.2.2. QOL

The EUROHIS-QOL 8-item index (European Health Interview Surveys) is a short version of the WHOQOL-BREF. It consists of 8 questions that are also included in the 26 questions of the WHOQOL-BREF [33]. All four domains (physical, psychological, social and environmental) are represented, each with two questions. A normative study in Germany showed good construct validity and reliability [34]. An adapted, easy-tounderstand sign language version of the EUROHIS-QOL 8-item index was administered to assess participants' self-rated QOL [35]. Fellinger et al. (2021) [35] demonstrated that reliable and valid self-reports of QOL can be obtained from adults who are deaf with mildto-moderate intellectual disability using standard inventories such as the EUROHIS-QOL adapted to the linguistic and cognitive levels of these individuals. The EUROHIS-QOL 8-item index score was computed as the mean score across the eight items, ranging from 1 (worst QOL) to 5 (best QOL). The test–retest reliability was good (0.75), and internal consistency showed a Cronbach's Alpha of 0.78.

#### 2.2.3. Maladaptive Behavior

The VABS-II includes two subscales for internalizing and externalizing maladaptive behavior. The two subscales are reported as v-scale scores. A v-scale score below 18 indicates a non-clinical level of maladaptive behavior; a score between 18 and 20 indicates an elevated level; and a score between 21 and 24 indicates a clinically significant level of maladaptive behavior [15].

#### *2.3. Data Collection*

Data collection took place between September 2017 and March 2018. Participants' clinical characteristics (i.e., type and degree of hearing loss; psychiatric, behavioral and neurological diagnoses) were extracted from the medical records of the individuals at the hospital St. John of God. The QOL self-reports were gathered through a structured interview between the resident and a sign language-competent staff member who was not directly involved in the care of the residents (non-involvement in direct care was considered important in order for the participants not to feel pressured to give answers that they thought would be preferred by the interviewer).

VABS-II data were collected for each participant by the staff psychologist in consultation with either a family member or the participant's primary caregiver. Primary caregivers serve the roles of coach, case manager, advocate and personal assistant for residents and were therefore thought to be particularly well-qualified to serve as informants for this study.

#### *2.4. Computing Intellectual Disability Domain Discrepancies*

Within the context of this paper, we use the term *intellectual disability domain discrepancy* to indicate that there is a substantial difference between the level of intellectual, social and/or practical adaptive functioning. For the purpose of this study, when comparing intellectual functioning with the social or practical domain, a difference of at least 15 points (=1 SD) between the IQ score (SON-R 6-40) and the socialization and daily living skills (DLS) standard scores indicates an intellectual disability domain discrepancy. When comparing the social and practical domains, a difference between the socialization and the DLS standard scores with a significance level of 0.05 according to the VABS-II manual indicates a domain discrepancy between these two domains.

#### *2.5. Statistical Analysis*

First, univariate analysis of the key variables was applied to describe intellectual disability domains, QOL and maladaptive behavior, as well as domain discrepancies. Next, Spearman's correlation was performed to test for a correlation between intellectual disability domains (social, practical and intellectual functioning), QOL and maladaptive behavior. To investigate whether there were significant differences in the means of selfreported QOL and internal and external maladaptive behavior with and without intellectual disability domain discrepancies, an independent samples *t*-test was performed.

#### **3. Results**

#### *3.1. Intellectual Disability Domains, QOL and Maladaptive Behavior*

Figure 1 shows the distribution of the median standard scores of (a) SON-R 6-40 intellectual functioning and (b) the three domains of Vineland-II adaptive functioning (practical, social and communication). Intellectual functioning emerged as the strongest domain, with a mean standard score of 67.31 (SD = 6.49) and no standard scores lower than 57 (see Table 2). The individuals also demonstrated a low level of practical functioning with a mean score of 48.97 (SD = 17.41), with more than half of the sample classified as having moderate or severe deficits. The social domain was the weakest domain with a mean score of 41.45 (SD = 19.66), indicating a moderate level of impairment according to the classification of the ICD-10 [31], and 12 (41.4%) individuals can be classified as having severe deficits in this domain. The communication domain of the Vineland-II, with a median standard score of 22, emphasizing the floor effect described earlier, was impossible to use as a proxy for the conceptual domain.

**Table 2.** Descriptive results for intellectual disability domains, QOL and maladaptive behavior.

*3.2. Correlations between the Intellectual Disability Domains and QOL and Maladaptive Behavior*

Table 3 shows the Spearman's correlation coefficients between the three domains. The social and practical domains are significantly positively correlated (r = 0.783, *p* = 0.000), as are the practical domain and intellectual functioning (r = 0.453, *p* < 0.05). The social domain and intellectual functioning are not significantly correlated (see Table 3). There are neither significant correlations between adaptive behavior and self-reported QOL nor significant relationships between adaptive behavior and maladaptive behavior, although correlations with social functioning approached the trend level of significance (*p* < 0.1).

**Table 3.** Zero-order correlation matrix among intellectual, social and practical functioning variables; quality of life; and maladaptive behavior (N = 29).

Spearman's correlation coefficient: † *p* < 0.1; \* *p* < 0.05, \*\* *p* < 0.001.

#### *3.3. Intellectual Disability Domain Discrepancies*

Almost two-thirds of the individuals had an intellectual disability domain discrepancy between their intellectual functioning level and the social domain (n = 19, 65.5%), and more than half had an intellectual disability domain discrepancy between their intellectual functioning and the practical domain (n = 17, 58.6%). About one-quarter of the individuals had an intellectual disability domain discrepancy between the social and the practical domains (n = 7, 24.1%), where in all cases the social domain was the weaker domain. Thus, participants' social adaptive skills were often poorer than their intellectual functioning and practical adaptive skills.

#### *3.4. Associations between Intellectual Disability Domain Discrepancies and Self-Reported QOL as Well as Maladaptive Behavior (Independent Samples t-Tests)*

When comparing participants with and without intellectual disability domain discrepancies, high mean QOL was endorsed across both groups, and no significant differences were found (see Table 4). Participants with a discrepancy between intellectual functioning and social domain had significantly higher levels of internalizing maladaptive behavior than the other groups (T = 1.889, *p* < 0.05).

**Table 4.** Mean differences in self-reported QOL and internal and external maladaptive behavior with and without intellectual disability domain discrepancies (independent samples *t*-test).

Self-reported QOL is indicated by a 5-point scale; \* = *p* < 0.05; maladaptive behavior is reported as v-scale scores: <18 indicates average level, 18–20 indicates elevated level and 21–24 indicates a clinically significant level.

#### **4. Discussion**

The aim of this study was to describe profiles of intellectual disability and domain discrepancies in a sample of adults who are prelingually deaf with mild and borderline cognitive impairment and to explore how these domains of intellectual disability are related with each other and associated with self-reported QOL and maladaptive behavior. Our findings provide a first indication of possible intellectual disability domain discrepancies among individuals with deafness and intellectual disability and highlight the value—as well as potential challenges or limitations—of DSM-5 s definition of intellectual disability for the deaf population. Furthermore, we investigated differences between those with and without domain discrepancies with respect to QOL and internalizing and externalizing maladaptive behavior.

Heterogeneous intellectual disability profiles were highly common among our participants, with only 24% showing no discrepancy between intellectual and adaptive functioning. In nearly two-thirds of the sample, intellectual disability domain discrepancies could be observed between intellectual functioning (65.5%) and both the practical (58.6%) and the social domain (65.5%). Domain discrepancy between the practical and social domain occurred in about one-fourth of cases (24.1%). Less than half of the sample had adaptive functioning levels in the practical and social domains that corresponded to their level of mild intellectual impairment, whereas severe levels of impairment were evident in the practical domain in 28% of the sample and in the social domain in 41%.

In our sample, the results of the communication subscales of the VABS-II, which were adapted but not originally designed for use in deaf populations, indicated severe deficits in 65.5% of the sample. Due to pronounced floor effects, the values of this domain were used neither as an equivalent for the conceptual domain nor for further calculations. Language is an important driver of acquiring social and practical skills above a rudimentary basal level [36], and the huge discrepancies seen in our sample with cognitive impairments may be due to the force multiplier effect of communication deprivation on the development of adaptive skills in this vulnerable population. These findings underscore how severe early childhood language deprivation impacts communication skills [10], even in our population where great effort has been taken to optimize access to communication through sign language in adult life. Other research in individuals with intellectual disabilities could show a strong association between communicative competences and QOL [37], which highlights the importance of access to language and communication. In contrast to the findings of Sparrow et al. 2005, in the present study with a sample who is prelingually deaf with mild cognitive deficits, the socialization domain appeared to be the weakest [15].

The relationship between intellectual functioning and the practical domain in our sample was moderately significant (r = 0.453, *p* < 0.05) and in line with the results of the meta-analysis of Alexander and Reynolds [14], whereas no significant correlations between intellectual functioning and the social functioning domain could be found in our sample.

Tassé [13] and Simoes et al. [26] both found a positive correlation between adaptive behavior and QOL in samples with mild-to-moderate intellectual disability. A similar effect is hinted at in our sample, with correlations trending toward statistical significance between social functioning and self-reported QOL (r = 0.354, *p* < 0.1), as well as a negative correlation between social functioning and internalizing maladaptive behavior (r = −0.351, *p* < 0.1). Conversely, neither intellectual functioning nor adaptive functioning in the practical domain were correlated with QOL or maladaptive behavior, a comparable finding to that observed by Graves et al. [18], who found no correlation between adaptive behavior and quality of life in adults with Down syndrome.

Having a statistically significant adaptive domain discrepancy between intellectual and social functioning was significantly correlated with higher levels of internalizing maladaptive behavior, a phenomenon that has also been observed in Autism Spectrum Disorder (e.g., [24,38]). Pending replication, one is tempted to query whether social connection is the critical ingredient in the positive adjustment and emotional well-being of individuals who are deaf (see, e.g., [39,40]), as well as individuals who are deaf and have intellectual disabilities, and we will pursue and welcome further inquiry in this area.

#### *Limitations*

We must also note this study's limitations. First and foremost, this is a small sample drawn from a highly enriched therapeutic residential care setting for adults who are deaf and have intellectual disabilities. Since this sample has only borderline-to-mild cognitive impairment, we make no claim to generalizability to the larger population of adults who are deaf with intellectual disability; much larger replication trials are needed.

Second, we must query whether the VABS-II, widely regarded as the "gold standard" adaptive measure in the majority of cases, is the most appropriate measure for this population. We therefore encourage further research in the service of formulating an optimal assessment battery both to gauge and, we hope, discover how to unlock these individuals' full potential. We would emphasize the importance of developing and validating a communication scale that is independent of (or less conflated with) solely spoken and auditory modalities.

#### **5. Conclusions**

Clearly, the assessment of intellectual disability transcends IQ, and we hope to inspire efforts toward an even higher level of measure refinement and collaborative research between investigators and participants. Underscoring the DSM-5 s incorporation of adaptive functioning into its definition of intellectual disability, our population of participants who were prelingually deaf with mild cognitive impairments had a broad array of strengths and challenges. Intellectual functioning emerged as a relative strength, whereas almost half our participants had severe deficits in the social domain. Critically, a higher level of internalizing maladaptive behavior was observed in those participants with a domain discrepancy between their intellectual and social functioning. We must acknowledge that, even with our best efforts in providing accessible therapeutic communities in adulthood, deficits in the social domain could not be fully compensated after histories marked by severe trauma and deprivation. This finding constitutes a strong case for the early prevention of communicative and social deprivation by providing full access to spoken and/or signed communication. Nevertheless, nuanced measurement of adaptive skills gives us a good opportunity to identify and target malleable factors to improve QOL in individuals who are deaf and have intellectual disability more broadly.

**Author Contributions:** Conceptualization, J.F. (Johannes Fellinger) and M.D.; methodology, J.E.; validation, J.F. (Johannes Fellinger), D.H., J.F. (Jason Fogler), J.E. and M.D.; formal analysis, J.E.; investigation, M.D. and J.F. (Johannes Fellinger); data curation, M.D.; writing—original draft preparation, J.E., J.F. (Jason Fogler), M.D., D.H. and J.F. (Johannes Fellinger); writing—review and editing, J.E., J.F. (Jason Fogler), M.D., D.H. and J.F. (Johannes Fellinger); supervision, J.F. (Johannes Fellinger); project administration, M.D.; funding acquisition, J.F. (Johannes Fellinger). All authors have read and agreed to the published version of the manuscript.

**Funding:** Supported by Johannes Kepler Open Access Publishing Fund.

**Institutional Review Board Statement:** The study was conducted in accordance with the Declaration of Helsinki and approved by the Ethics Committee of the Hospital of St. John of God in Linz (approval number: 14-08).

**Informed Consent Statement:** Informed consent was obtained from all subjects involved in the study or their legal guardians.

**Data Availability Statement:** Data are not publicly available due to data protection issues.

**Acknowledgments:** We would like to thank Johannes Kepler Open Access Publishing Fund.

**Conflicts of Interest:** The authors declare no conflict of interest.

#### **References**

## *Article* **Withdrawing Antipsychotics for Challenging Behaviours in Adults with Intellectual Disabilities: Experiences and Views of Prescribers**

**Gerda de Kuijper 1,2,\*, Joke de Haan 1, Shoumitro Deb 3 and Rohit Shankar 4**

**Abstract:** International current best practice recommends the discontinuation of antipsychotics for challenging behaviours in people with intellectual disabilities (ID), due to lack of evidence of efficacy and risks of harmful side-effects. In clinical practice, discontinuation may be difficult. The aim of this study was to gain insight into prescribers' practice by investigating their experiences with the discontinuation of long-term antipsychotics for challenging behaviour. From professionals' associations thirty-four registered ID physicians, psychiatrists and specialist mental healthcare nurses were recruited who completed an online questionnaire in this survey–study. Almost all participants had attempted to deprescribe antipsychotics for their patients with ID. Sixty-five percent of participants achieved complete discontinuation in 0–25% of their patients, but none in over 50%. Barriers were a lack of non-pharmaceutical treatments for challenging behaviours and caregivers' and/or family concern. Seventy percent of participants indicated that their institutions had encouraged implementing their discontinuation policies in line with the new Dutch Act on Involuntary care and a new Dutch multidisciplinary guideline on problem behaviour in adults with ID. Support and facilitation of clinicians from institutions' managers and political and professional bodies may be helpful in further implementation of best practice in the treatment of challenging behaviour in people with ID.

**Keywords:** intellectual disabilities; antipsychotics; challenging behaviour; discontinuation; prescribers' policies; survey

#### **1. Introduction**

The rates of challenging behaviours displayed by people with intellectual disabilities (ID) vary from 18% in community populations to 85% in people with profound ID who live in institutions [1–3]. The onset and maintenance of challenging behaviours in individuals with ID are associated with biological, psychological and environmental factors [1,2,4–6]. Behaviours include outwardly directed behaviours like aggressive-destructive behaviour, inappropriate (sexual) behaviour and disruptive behaviours. It also includes hyperactivity, irritability, lethargy and self-injurious, stereotypic and withdrawn behaviours [2,7,8]. Challenging behaviours may vary in intensity and be persistent [9–12]. When individuals present with challenging behaviour, this may negatively influence their quality of life [13,14] and social participation [15]. Diagnosis and management require a multidisciplinary and integrative approach as the causes of these behaviours are multi-factorial (physical, genetic, psychiatric, psychological, social, environmental, etc.) [3,6,16].

**Citation:** de Kuijper, G.; de Haan, J.; Deb, S.; Shankar, R. Withdrawing Antipsychotics for Challenging Behaviours in Adults with Intellectual Disabilities: Experiences and Views of Prescribers. *Int. J. Environ. Res. Public Health* **2022**, *19*, 17095. https://doi.org/10.3390/ ijerph192417095

Academic Editor: Paul B. Tchounwou

Received: 11 October 2022 Accepted: 15 December 2022 Published: 19 December 2022

**Publisher's Note:** MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations.

**Copyright:** © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).

Psychotropic drugs, especially antipsychotics, are often prescribed for the management of challenging behaviours [17–22]. Significantly higher levels of antipsychotic drug prescribing occur to manage challenging behaviour in people with ID and/or autism [23]. However, the effectiveness of psychotropic drugs for the treatment of challenging behaviours in people with ID has not been proven [24–27]. Moreover, in this population, the risk of side-effects like diabetes, cardio-vascular disorders, sedation and movement disorders is considerable, especially in the case of long-term use of antipsychotics [28–31]. It is recommended by all good practice guidelines that the treatment of challenging behaviours should be, in the first place, non-pharmacological, i.e., psychosocial and behavioural. Practitioners should only prescribe psychotropic drugs after careful weighing of the potential positive and negative effects of this medication and preferably just for the short-term (max. 6–12 weeks). For example, prescription may be beneficial to overcome crisis situations when the person or others are at risk of serious harm, or in conjunction with non-pharmacological interventions [16,32,33].

Although it is recommended that long-term off-label psychotropic drug prescription should be discontinued especially antipsychotics, they are still frequently prescribed for the treatment of challenging behaviours [34–36]. This may, at least partially be, because of failures of successful discontinuation of antipsychotics due to worsening of behaviour upon drug withdrawal [37]. Besides user-related factors, like the occurrence of withdrawal symptoms, symptoms of previously not-recognized mental or physical disorders or other health problems, and staff-related factors, are associated with unsuccessful withdrawal of antipsychotics [38]. For example, staff may experience difficulties in the management of changes in their clients' behaviour, may have negative feelings towards clients' behaviour or lack knowledge or have unrealistic expectations about the effects of psychotropic drugs [39,40]. The involvement of all stakeholders, including the patients and their relatives, seems a key-element in the achievement of successful changes in prescription policies [41].

In some countries, initiatives have been taken to facilitate the deprescribing of antipsychotics for challenging behaviours. For example, in the UK, the "stopping over medication of people with a learning disability, autism or both with psychotropic medicines" (STOMP) is now incorporated within the NHS England long-term plan [42]. The development of a structured pathway with the involvement of all stakeholders led to successful discontinuation in 46% of cases and dose reductions of over 50% in another 11% [43]. A survey among UK psychiatrists about changes in prescription policies as a result of the STOMP initiative showed that the prescriptions practice has changed. The UK psychiatrists are less likely to initiate new prescriptions of antipsychotics. However, complete antipsychotic discontinuation in over 50% of their patients was achieved by only 4.5% of responding psychiatrists [44].

In The Netherlands, Vilans, a knowledge centre on long-term care has conducted a project (2015–2019) to reduce inappropriate psychotropic prescribing in the elderly with dementia and in people with ID and high care needs. In this project, an e-learning on psychotropic drug use in people with ID for support professionals has been developed [45]. Moreover, in The Netherlands, in December 2019, a new multidisciplinary guideline on challenging behaviour [46] and, in January 2020, a new Dutch Act on Involuntary care was published. In both, the prescription of psychotropic drugs for challenging behaviours outside guideline recommendations is regarded as restricted practice. A study among Dutch ID physicians on their experiences with the guideline and new Act showed that they regarded the Act as supportive of reducing the off-label prescriptions of psychotropics. However, because of organisational difficulties, the feasibility of implementing the guideline and new Act is not always possible in practice [47].

In The Netherlands, there are 250 registered ID physicians. Most of them take care of people with ID and complex needs, including people with multiple disabilities and/or behavioural problems.

There are approximately 15–20 ID specialized mental healthcare outpatient clinics spread over The Netherlands. Psychiatrists in mainstream mental healthcare organizations or who have their own private practice may also be consultants at ID institutions. In Dutch mental healthcare, specialist nurses monitor the use of the psychotropic drugs and are authorized to stop or change a prescription in consultation with the psychiatrist who initiated the prescription. In community care, GPs may provide repeat prescriptions and/or the monitoring of psychotropic drug use; however, mostly, they refer to ID physicians or specialized ID mental healthcare when discontinuation or change in medication is necessary. The total number of mental healthcare professionals affiliated with the Dutch ID mental healthcare outpatient clinics, authorized to prescribe psychotropic medication, is unknown. We estimate 100–150 such prescribers based on the number of ID mental healthcare clinics and consultant -psychiatrists specializing in people with ID in The Netherlands.

The present study aimed to gather information about facilitators and barriers to the successful discontinuation of antipsychotic drugs when used for challenging behaviours in people with ID. We conducted a survey, similar to the UK survey [44], about experiences with antipsychotic drug discontinuation among ID physicians, psychiatrists and specialist nurses in The Netherlands who were responsible for the psychotropic drug prescriptions for their patients with ID. We also asked whether their antipsychotic prescribing practice had changed because of the new guideline and new Act.

#### **2. Materials and Methods**

#### *2.1. Design*

This was a cross-sectional study including a questionnaire survey among Dutch prescribers of psychotropic medications for people with ID.

#### *2.2. Participants and Settings*

Participants were registered ID physicians affiliated with ID institutions and institutions' outpatient clinics or having their own practice, and psychiatrists or specialist nurses affiliated with ID-specialized mental healthcare outpatient clinics or having their own practice.

#### *2.3. Materials*

The questionnaire items were adapted for the Dutch ID healthcare system from a survey which was developed in a recent study of UK psychiatrists' views on the rationalization of psychotropic use among people with ID [44]. The survey answer options of items were multiple choice with an open field for comments. Supplementary Materials shows the items of the questionnaire and corresponding answer options. The forty-two questionnaire items were grouped under five themes similar to those in the UK survey. These themes included:

#### *2.4. Procedures*

The participants were recruited from the ID physicians affiliated with the Dutch Intellectual Disabilities physicians' association (NVAVG), psychiatrists affiliated with the Dutch Psychiatrists Association (NVvP) and nurses affiliated with the Dutch specialist nurse care association (VenVNVS). We had to approach all the Dutch psychiatrists and specialist nurses as there is no Register of those who specifically specialize in ID mental healthcare.

The survey was open between 19 February and 1 May 2021. A reminder was sent three weeks before the closing date. A news item with the link to the questionnaire was also placed on the websites of the professionals' associations. Members of the professional organisations/potential responders received an explanatory letter with a link to the program Qualtrics where they could fill in the questionnaire. On average, it took participants 30–45 min to complete the questionnaire.

#### *2.5. Ethics*

All responders in the survey participated voluntarily. All data were collected, stored, and safeguarded anonymously, according to the European Act on Protection of Personal Information, in The Netherlands, which was ratified in 2018.

#### *2.6. Analyses*

SPSS 26 was used to analyse the survey data. Descriptive statistics were used to calculate frequencies of respondents' characteristics and answer categories as per the multiple-choice questions. Pearson Chi-Square was used to compare characteristics and answer categories between a group consisting of ID physicians on the one hand and psychiatrists and ID specialist mental healthcare nurses on the other.

#### **3. Results**

We present the results by the forming of two clusters encompassing the five themes of the questionnaire as described under Methods/Materials (themes 1 and 2, and themes 3, 4 and 5 respectively). The data and analyses of all the 42 questions and corresponding answers (see Supplementary Materials) are available on request.

#### *3.1. Participants and Prescription Patterns (Themes 1 and 2 of the Questionnaire)*

Twenty-one of the 250 ID physicians registered in The Netherlands and thirteen of the estimated 100–150 mental healthcare professionals prescribing psychotropics to patients with ID (i.e., psychiatrist or specialist mental healthcare nurse) completed the questionnaire (response rate of 8.5% and estimated response rate 8.6–13%, respectively). The exact response rate of the ID mental healthcare professionals could not be calculated because there are no data on the total number of those in ID mental healthcare in The Netherlands.

Twelve (35%) of the total 34 participants reported that their working experience in the field was for less than 10 years, 10 (30%) had worked in the field for 10–19 years, 11 (32%) 20–29 years, and 1 (3%) for more than 30 years. Five (15%) of the participants stated that 0–25% of their patients, 17 (50%) that 25–50%, 5 (14%) that 50–75% and 4 (12%) that 75–100% of their patients with ID were prescribed antipsychotics. Three participants (9%) could not provide the percentage.

#### *3.2. Participants' Policies and Experiences (Themes 3, 4 and 5 of the Questionnaire)*

Table 1 shows the results of participants' practice and experience regarding the deprescribing of antipsychotics in their patients with ID. Participants attempted to deprescribe antipsychotics in a variable part of their patients. In Table 1, the number and percentage of participants is shown who attempted to deprescribe antipsychotics in a certain proportion of their patients.

A considerable number of participants did not attempt to withdraw antipsychotics in their patients with ID and challenging behaviour when there was a clear diagnosis of a psychiatric disorder which justified the prescription. This diagnosis was confirmed recently (i.e., in the two preceding years) in more than half of the total number of respondents (55%). A significantly lesser proportion of ID physicians (38%) compared with ID mental healthcare professionals (ID psychiatrists and nurses) (83%) confirmed the psychiatric diagnosis (*p* = 0.01). Only eight (24%) prescribers confirmed psychiatric diagnosis themselves (ID physicians 10%, ID healthcare professionals 50%, the difference not significant). In addition, there were differences between these two groups with regard to the mean duration of the discontinuation trajectory, which was, on average, significantly longer in ID physicians (0–6 months, 9% in ID physicians versus 8% in ID mental healthcare professionals, 6–12 months, 24% versus 77%, 12–18 months, 47% versus 0%, and >18 months in 19% versus 15%, respectively, *p* = 0.01)

**Table 1.** Practice and experience of intellectual disability (ID) physicians and ID mental healthcare professionals # who completed the survey (N = 34 participants) in deprescribing antipsychotics for challenging behaviours.