the vulnerability of elderly hospital patients is characterised by simultaneously occurring somatic , psychological , and social problems , which may result in problems in cognitive functioning , mood , behaviour , activities of daily life , and , consequently , in declining quality of life .
first , the choices of nursing interventions are substantially influenced by the patient 's cognitive abilities .
the patient 's cognitive abilities determine the provision of nursing care to a large extent as they influence communication , the support to be given in daily life activities , the recognition and treatment of other nursing problems ( e.g. , pain , behavioural problems ) , and discharge policy [ 13 ] .
the nurse 's approach to individual patients is also largely influenced by the type of cognitive problem . in case of memory problems , for example , information is repeated or written down ; in case of problems in sustaining attention , a quiet environment is offered ; and in case of executive problems , information is kept simple .
for example , memory problems are often the first sign of alzheimer 's disease , whereas loss of awareness may indicate frontotemporal dementia , and hallucinations suggest delirium and dementia with lewy bodies .  
cognitive functioning is a term used to address the wide area of human information processing .
the concept of cognitive functioning is operationalized by breaking it down into several cognitive domains .
however , there is no uniform way to classify the cognitive domains ; different authors organise the cognitive domains in different ways [ 46 ] . cognitive decline may occur due to age - related factors , depression , delirium , dementia , and in combination with serious somatic health problems .
recognition of delirium is most important because of its high incidence rate and reversible character , for example , by means of the confusion assessment method ( cam ; ) and the delirium observation scale ( dos ; ) .
however , comprehensive cognitive assessment still needs to be carried out as other types of brain dysfunction might occur , such as dementia or brain injury . a diagnosis
is then based on medical history , neurological assessment , neuropsychological assessment , neuroimaging , complaints of patient , and behavioural symptoms .
direct observation of the patient 's cognitively mediated abilities complements cognitive assessment [ 2 , 9 ] .
daily observation of the patient covers 24 hours a day and may last for several days .
it is based on informal interactions between the patient and nurse , for example , when taking a bath , having breakfast , during transfers , or when interacting with other patients .
the patient 's cooperation is not required , and observation can be conducted even when patients are too ill to undergo neuropsychological testing . unlike testing , which assesses cognitive abilities under optimal experimental conditions , direct observation assesses a person 's cognitive abilities in daily life .
results of daily observation are therefore of high ecological validity as they are linked to the natural setting of daily life and do not depend on one specific test moment [ 9 , 10 ] .
observation may improve the reliability of cognitive assessment if serial observations are recorded on several consecutive days .
furthermore , observation fits very well into the nursing practice , because information is directly accessible during patient care encounters .
one problem with direct observation is its standardisation . yet , well - validated observation scales are rather scarce , although some good examples exist in geriatrics , for example , for depression , pain , agitation , dementia , and as mentioned above , for delirium .
we searched the literature for direct observation scales for cognition abilities , excluding , however , delirium screening instruments .  
we found instruments which assess cognitive functioning in a limited way ( not divided into subscales of cognitive domains : e.g. , the old ) , facilitate just one or two cognitive domains ( e.g. , the nosger ) , or are too specific for nurses ( the a - one ) .
furthermore , many of them also involved issues such as mood or behavioural problems ( e.g. , moses and nosger ) .
we therefore concluded that there is no valid observation scale available for nurses to comprehensively assess cognitive functioning in relation to possible dementia or brain injury .   in daily practice
, this means that individual nurses observe cognitive functioning in patients in a nonmethodological way .
this undermines the reliability and validity of the information obtained , as demonstrated in two studies on dutch geriatric hospital wards [ 3 , 19 ] .
the nurses in these studies assessed different cognitive domains per patient , aimed at different goals .
the aim of this study was to develop an observation scale with an acceptable level of content validity which assesses elderly patients ' cognitive abilities in a comprehensive manner , including a wide range of cognitive domains .
the resulting nurses observation scale for cognitive abilities ( nosca ) had to fulfil certain preconditions : it should be suitable for observation of the population of geriatric patients admitted in acute care hospitals ;   it should structure around - the - clock observations by nurses and possibly include all interactions naturally occurring between patient and nurse ( e.g. , bathing , meal times or transfers , small talk , informing , educating ) ;   it should serve goals important in daily practice , that is , it should enable tailoring to individual ( nursing ) care plans , contribute to the diagnostic process , or facilitate further neuropsychological examination .
the works by haynes , polit and beck , streiner and norman , and foreman et al .   on the development of ( cognitive ) measurement scales constituted the point of departure for our study .
they all underpin the necessity to explicitly decide on the aim and context of the measurement instrument to be developed .
content validity concerns the conceptualisation of the content and the degree to which the scale represents the concept .
content validity is the degree to which an instrument has an appropriate number of items for the construct being measured . as no uniform way to classify cognitive domains was found in the literature , a panel of experts was required to evaluate the content validity of the scale developed .
we obtained a written judgment from the experts concerning the nosca construct and items by means of the delphi technique .
in several rounds during which experts ' preferences were integrated , consensus was achieved concerning the nosca construct : the cognitive domains ( phase 1 ) and items ( phase 2 ) . in phase 3
we proceeded from the definition of cognitive function as cited by a nursing protocol found in the literature , which was based on the work of lezak :  cognitive functioning encompasses the processes by which an individual perceives , registers , stores , retrieves and uses information  . as the scale had to have a firm theoretical basis and no consensus was found in the geriatric , psychiatric , or neuropsychological field , we selected the more general health - based international classification of functioning ( icf ) .
the icf includes a classification system of functions , in which chapter 1 states the mental functions . some of these mental functions relate to cognitive functions . to enhance reliability ,
items had to be written for observable patient activities or behaviour , noticeable for all observers , so that bias in the observer 's interpretation would be minimised . as the patient 's cognitive functioning varies depending on the moment of the day , type of activity , or interaction with others , we preferred more than one observation .
the observation should take place twice a day during two consecutive days in order to obtain sufficiently reliable outcome and should also account for inter - daily variation . to improve reliability
, it was required that the scale be completed at the end of every shift .
the multidisciplinary panel consisted of 16 experts and was composed of geriatric nurses ( 2x ) , advanced nurses in geriatrics ( 5x ) , one nurse lecturer in geriatrics , geriatricians ( 3x ) , neuropsychologists ( 4x ) , and one occupational therapist ( see table 2 ) .
all of them had many years of clinical practice experience with elderly people and were in some way experts in assessing cognitive functioning .
of the advanced nurses , two had additional experience in developing a measurement instrument for assessing elderly people , two nurses were familiar with the icf , and four of them had published ( internationally ) on cognitive functioning .
three out of the four neuropsychologists had experience in developing a measurement instrument and had published in international journals .
the geriatricians were selected because of their clinical expertise and the research they had conducted . of the originally invited experts , only one refused because the delphi rounds would be too time - consuming .
all the experts received information about the objective of the observation scale , the setting , and the theoretical framework . 

phase 1 : domains includedin this phase , the construction of the scale was established by means of the 1st and 2nd delphi rounds . the aim was to determine the cognitive domains to be included in the scale . in the 1st delphi round , nine of the cognitive domains mentioned in chapter 1 of the icf
this information also included the icf definition of the cognitive domain and 19 icf subdomains .
furthermore , all functions as described in this chapter were presented , so experts were able to judge the representativeness of the nine domains proposed .
the experts were requested to respond on the following : the relevance of the icf domain ( also including the formulation of the icf label and icf definition ) and the relevance of the subdomain ( also including the formulation of the icf label and icf definition ) , representing all important cognitive domains .
it was required that at least 70% of the experts agree that a proposed cognitive domain should be included .
suggestions from individual experts to rephrase or alter certain parts or to include new ( sub)domains were presented to the panel in the second round . 
  in this phase ,
the construction of the scale was established by means of the 1st and 2nd delphi rounds .
the aim was to determine the cognitive domains to be included in the scale . in the 1st delphi round , nine of the cognitive domains mentioned in chapter 1 of the icf
this information also included the icf definition of the cognitive domain and 19 icf subdomains .
furthermore , all functions as described in this chapter were presented , so experts were able to judge the representativeness of the nine domains proposed .
the experts were requested to respond on the following : the relevance of the icf domain ( also including the formulation of the icf label and icf definition ) and the relevance of the subdomain ( also including the formulation of the icf label and icf definition ) , representing all important cognitive domains .
it was required that at least 70% of the experts agree that a proposed cognitive domain should be included .
suggestions from individual experts to rephrase or alter certain parts or to include new ( sub)domains were presented to the panel in the second round . 

phase 2 : item selectionin this phase , the items of the scale were determined by means of the 3rd and 4th delphi rounds .
central in this phase was the question as to whether an item was relevant to a domain or subdomain and whether the items sufficiently represented the domain .
the items presented to the panel were mainly derived from other observation scales ( see table 1 ) .
all the items were reformulated using the same sentence structure , for example ,  the patient is able to locate his / her own bed  .
furthermore , we placed the items into matching domains and subdomains . in the 3rd round , we presented the panel with the 173 items , divided across the domains and subdomains . the experts were requested to respond on the following : the relevance of the item and the priority of the item , representing all important items .
then , the items approved were checked for interdependency . when it turned out that too many items were approved , we selected the best observable behaviour or activity .
subsequently , the approved items were checked again in order to assess whether they differentiated from items in the other cognitive domains . if they did not , we selected the items which seemed to be most appropriate for certain domains
. finally , the suggestions made by the experts concerning the rephrasing of items or inclusion of new items were incorporated.in the 4th delphi round , items which were still under discussion , newly suggested , or located in another domain or subdomain were reevaluated by the experts . 
  in this phase ,
the items of the scale were determined by means of the 3rd and 4th delphi rounds .
central in this phase was the question as to whether an item was relevant to a domain or subdomain and whether the items sufficiently represented the domain .
the items presented to the panel were mainly derived from other observation scales ( see table 1 ) .
all the items were reformulated using the same sentence structure , for example ,  the patient is able to locate his / her own bed  .
furthermore , we placed the items into matching domains and subdomains .   in the 3rd round
, we presented the panel with the 173 items , divided across the domains and subdomains .
the experts were requested to respond on the following : the relevance of the item and the priority of the item , representing all important items .
then , the items approved were checked for interdependency . when it turned out that too many items were approved , we selected the best observable behaviour or activity .
subsequently , the approved items were checked again in order to assess whether they differentiated from items in the other cognitive domains .
if they did not , we selected the items which seemed to be most appropriate for certain domains . finally , the suggestions made by the experts concerning the rephrasing of items or inclusion of new items were incorporated . in the 4th delphi round , items which were still under discussion ,
newly suggested , or located in another domain or subdomain were reevaluated by the experts . 

phase 3 : pretestin this phase , the feasibility of the observation scale was tested in a small study . over a period of two weeks
, nurses from one geriatric ward were asked to complete the observation scale on the basis of their observation of a single patient during their shift .
the nurses were asked for comments on the instructions and on the observation scale . some of these comments were subsequently processed .
after seven nurses had provided their comments , no further suggestions for adjustments were made . 
  in this phase
, the feasibility of the observation scale was tested in a small study . over a period of two weeks
, nurses from one geriatric ward were asked to complete the observation scale on the basis of their observation of a single patient during their shift .
the nurses were asked for comments on the instructions and on the observation scale . some of these comments were subsequently processed .
after seven nurses had provided their comments , no further suggestions for adjustments were made .

 phase 1 : domains includedin the first two delphi rounds , the response from the 16 panel members was 100% .  
table 3 presents an overview of the panel 's acceptance of the domains and subdomains and the suggestions they made . after the 1st delphi round ,
all nine proposed domains were accepted ( > 80% agreement ) , as well as 16 out of the 19 proposed subdomains .
the response on the consciousness domain showed insufficient consensus : although 81% of the experts saw this domain as part of the cognitive function scale , several experts also suggested rephrasing because consciousness is only a prerequisite for cognitive functioning and should therefore have another position in the observation scale compared to the other cognitive domains .
after the 2nd delphi round , five out of the nine newly suggested subdomains were accepted by the panel ( > 80% agreement ) , see table 3 .
there was 81% agreement that consciousness should have a distinct place in the observation scale .
next , as suggested by experts in the first round , the subdomain of content of thoughts was added to the 2nd round , and although 81% of the panel agreed to include this subdomain , 64% wished to rephrase the items concerned .
the panel was therefore consulted by email on the question of whether or not these two subdomains should be included .
thirteen out of the 16 experts responded , and it was concluded that the subdomain of dividing attention should not be included ( 56% agreed ) .
it was also concluded that the subdomain of content of thoughts should be reformulated ( 85% agreed).in sum , after two delphi rounds and one follow - up email , the panel reached consensus on the construct of cognitive function by means of 8 domains and 17 subdomains ( see table 4 ) .
furthermore , the domain of consciousness ( consisting of two subdomains ) was considered a prerequisite for cognitive functioning , which should therefore be assessed beforehand . 
  in the first two delphi rounds , the response from the 16 panel members was 100% .  
table 3 presents an overview of the panel 's acceptance of the domains and subdomains and the suggestions they made . after the 1st delphi round ,
all nine proposed domains were accepted ( > 80% agreement ) , as well as 16 out of the 19 proposed subdomains .
the response on the consciousness domain showed insufficient consensus : although 81% of the experts saw this domain as part of the cognitive function scale , several experts also suggested rephrasing because consciousness is only a prerequisite for cognitive functioning and should therefore have another position in the observation scale compared to the other cognitive domains .
after the 2nd delphi round , five out of the nine newly suggested subdomains were accepted by the panel ( > 80% agreement ) , see table 3 .
there was 81% agreement that consciousness should have a distinct place in the observation scale .
next , as suggested by experts in the first round , the subdomain of content of thoughts was added to the 2nd round , and although 81% of the panel agreed to include this subdomain , 64% wished to rephrase the items concerned .
the panel was therefore consulted by email on the question of whether or not these two subdomains should be included .
thirteen out of the 16 experts responded , and it was concluded that the subdomain of dividing attention should not be included ( 56% agreed ) .
it was also concluded that the subdomain of content of thoughts should be reformulated ( 85% agreed ) . in sum , after two delphi rounds and one follow - up email , the panel reached consensus on the construct of cognitive function by means of 8 domains and 17 subdomains ( see table 4 ) .
furthermore , the domain of consciousness ( consisting of two subdomains ) was considered a prerequisite for cognitive functioning , which should therefore be assessed beforehand . 

phase 2 : item selectionin the 3rd and 4th delphi rounds , 15 and 16 out of the 16 panel members responded , respectively . after the 3rd round , it turned out that 58 of the 173 items were deemed to be relevant ( > 70% agreement ) .
16 items were excluded , which left us with a selection of 42 items . although these 42 items were accepted for the observation scale , the experts suggested rephrasing of seven items and relocating one item to another domain .
all in all , in the 4th round , 45 items were presented to the panel of which eleven were to be judged again on relevance , rephrasing , and representativeness .
after the 4th round , the panel accepted nine out of the eleven items as being relevant to the new observation scale and well - formulated ( > 70% agreement ) . 
  in the 3rd and 4th delphi rounds , 15 and 16 out of the 16 panel members responded , respectively .
after the 3rd round , it turned out that 58 of the 173 items were deemed to be relevant ( > 70% agreement ) .
16 items were excluded , which left us with a selection of 42 items . although these 42 items were accepted for the observation scale , the experts suggested rephrasing of seven items and relocating one item to another domain .
all in all , in the 4th round , 45 items were presented to the panel of which eleven were to be judged again on relevance , rephrasing , and representativeness .
after the 4th round , the panel accepted nine out of the eleven items as being relevant to the new observation scale and well - formulated ( > 70% agreement ) . in sum , after the 3rd and 4th rounds , the observation scale consisted of 39 items , divided across 8 domains and 17 subdomains , preceded by 4 items for the domain of consciousness as a condition for cognitive functioning ( see table 5 ) . 

please read the following information about the nosca 
 aim : 
 with this observation list , nurses can gain an impression of whether a patient has cognitive problems and if so , in which domains.these observations will be used to ( a ) contribute to the diagnostics at the multidisciplinary meeting and ( b ) to help determine the nursing interventions ( approach form , information , family education ) . 


instructions : 
 before starting your shift , read the nosca items so that you can make targeted observations and if necessary , induce behaviour ( e.g. , start a conversation , read a text , get dressed , etc.).create the most optimal conditions for the patient ( glasses on , hearing aid working).make observations over a period of two consecutive days , in the day shifts and evening shifts .
research has shown that more than four observation periods do not lead to better information.record the observations per shift , so that the report is as reliable as possible . 

 filling in the form : 
 put a circle around the correct answer in accordance with your observations during one shift . 
repeatedly  means that the behaviour occurred repeatedly during your shift.put a circle around the question mark  ?
 if the behaviour could not be observed because the situation did not arise ( e.g. , because the patient did not read anything ) . also put a circle around the question mark  ?
 if the patient could not display certain behaviour ( e.g. , the patient could not put on his / her clothes in the correct order , because he / she can not dress independently due to a physical disability ) . 


calculate the average score per subscale , representing a cognitive domain , and note it on the summary sheet ( range 03 points ) .
the nosca overall score is calculated by the sum of the eight domains ( range 024 points).norm values of the subscales : lower scores indicate less cognitive abilities : 
 3 means that no problems were observed;2 means that problems sometimes arose;1 means that problems usually arose;0 means that problems arose repeatedly . 



 

aim : 
 with this observation list , nurses can gain an impression of whether a patient has cognitive problems and if so , in which domains.these observations will be used to ( a ) contribute to the diagnostics at the multidisciplinary meeting and ( b ) to help determine the nursing interventions ( approach form , information , family education ) . 


instructions : 
 before starting your shift , read the nosca items so that you can make targeted observations and if necessary , induce behaviour ( e.g. , start a conversation , read a text , get dressed , etc.).create the most optimal conditions for the patient ( glasses on , hearing aid working).make observations over a period of two consecutive days , in the day shifts and evening shifts .
research has shown that more than four observation periods do not lead to better information.record the observations per shift , so that the report is as reliable as possible . 

 filling in the form : 
 put a circle around the correct answer in accordance with your observations during one shift . 
repeatedly  means that the behaviour occurred repeatedly during your shift.put a circle around the question mark  ?
 if the behaviour could not be observed because the situation did not arise ( e.g. , because the patient did not read anything )
 if the patient could not display certain behaviour ( e.g. , the patient could not put on his / her clothes in the correct order , because he / she can not dress independently due to a physical disability ) . 


calculate the average score per subscale , representing a cognitive domain , and note it on the summary sheet ( range 03 points ) .
the nosca overall score is calculated by the sum of the eight domains ( range 024 points).norm values of the subscales : lower scores indicate less cognitive abilities : 
 3 means that no problems were observed;2 means that problems sometimes arose;1 means that problems usually arose;0 means that problems arose repeatedly . 


 
 with this observation list , nurses can gain an impression of whether a patient has cognitive problems and if so , in which domains.these observations will be used to ( a ) contribute to the diagnostics at the multidisciplinary meeting and ( b ) to help determine the nursing interventions ( approach form , information , family education ) . 
  with this observation list
, nurses can gain an impression of whether a patient has cognitive problems and if so , in which domains .
these observations will be used to ( a ) contribute to the diagnostics at the multidisciplinary meeting and ( b ) to help determine the nursing interventions ( approach form , information , family education ) . 
 before starting your shift ,
read the nosca items so that you can make targeted observations and if necessary , induce behaviour ( e.g. , start a conversation , read a text , get dressed , etc.).create the most optimal conditions for the patient ( glasses on , hearing aid working).make observations over a period of two consecutive days , in the day shifts and evening shifts .
research has shown that more than four observation periods do not lead to better information.record the observations per shift , so that the report is as reliable as possible . 
  before starting your shift , read the nosca items so that you can make targeted observations and if necessary , induce behaviour ( e.g. , start a conversation , read a text , get dressed , etc . ) .
create the most optimal conditions for the patient ( glasses on , hearing aid working ) .
make observations over a period of two consecutive days , in the day shifts and evening shifts .
research has shown that more than four observation periods do not lead to better information .
record the observations per shift , so that the report is as reliable as possible . 

put a circle around the correct answer in accordance with your observations during one shift . 
repeatedly  means that the behaviour occurred repeatedly during your shift.put a circle around the question mark  ?
 if the behaviour could not be observed because the situation did not arise ( e.g. , because the patient did not read anything )
 if the patient could not display certain behaviour ( e.g. , the patient could not put on his / her clothes in the correct order , because he / she can not dress independently due to a physical disability ) . 
 
put a circle around the correct answer in accordance with your observations during one shift . 
 if the behaviour could not be observed because the situation did not arise ( e.g. , because the patient did not read anything )
 if the patient could not display certain behaviour ( e.g. , the patient could not put on his / her clothes in the correct order , because he / she can not dress independently due to a physical disability ) . 

the observations over four shifts lead to one conclusion . calculate the average score per subscale , representing a cognitive domain , and
the nosca overall score is calculated by the sum of the eight domains ( range 024 points).norm values of the subscales : lower scores indicate less cognitive abilities : 
 3 means that no problems were observed;2 means that problems sometimes arose;1 means that problems usually arose;0 means that problems arose repeatedly . 

 
the observations over four shifts lead to one conclusion . calculate the average score per subscale , representing a cognitive domain , and
the nosca overall score is calculated by the sum of the eight domains ( range 024 points ) .
norm values of the subscales : lower scores indicate less cognitive abilities : 
 3 means that no problems were observed;2 means that problems sometimes arose;1 means that problems usually arose;0 means that problems arose repeatedly . 
 
3 means that no problems were observed ; 2 means that problems sometimes arose ; 1 means that problems usually arose ; 0 means that problems arose repeatedly . 

phase 3 : pretestthe feasibility of the concept of the observation scale was tested seven times consecutively .
five times improvements were made for the sake of clarity ; the last two tests showed no need for adjustments .
in general , nurses had no difficulties filling in the form and it took them only a few minutes per patient per shift .
the instructions were changed several times , and the layout of the items was improved , resulting in a more concise and clear text . 
 
five times improvements were made for the sake of clarity ; the last two tests showed no need for adjustments .
in general , nurses had no difficulties filling in the form and it took them only a few minutes per patient per shift .
the instructions were changed several times , and the layout of the items was improved , resulting in a more concise and clear text .
the object of this study was to develop an observation scale in which cognitive abilities are assessed in a comprehensive manner , and which has an acceptable level of content validity .
we succeeded in designing the nurses ' observation scale cognitive abilities ( nosca ) , in which cognitive functioning is classified into eight domains , 17 subdomains , and 39 items , preceded by 4 items on the domain of consciousness .
the content validity of the nosca , as a measurement of the degree to which the scale represents the concept of cognitive functioning , is high for two reasons .
first , the minimum agreement between the panel members was 70% , and often higher on certain domains and items .
second , after the fourth delphi round , consensus was reached that no domains or items were lacking . in the preceding delphi rounds ,
the panel had made suggestions for including new domains and items , and some were accepted in the next delphi round .
the strength of our procedure was that the panel members represented four disciplines ( nursing , neuropsychology , geriatrics and speech , therapy ) .
thus , the quality of the panel was enhanced because each discipline with its specific focus and knowledge of the concept of cognitive functioning provided specific input for the observation scale . an equally strong point of the nosca and its development is that the scale is based on the icf 's theoretical framework .
although the icf is not a cognitive concept but a general classification of functioning , it proved to be very suitable for the purpose of our study and probably will increase acceptability in the field .  
the method we used had only one drawback : in designing the nosca , we were required , due to lack of consensus on the concept of cognitive functioning in the literature , to develop consensus by means of the delphi technique .
the disadvantage of this technique is that consensus depends on the current state of the art in the professional disciplines and that , through the years , the state of art will further develop .
particularly as a result of the new technique of neuroimaging , it is expected that the knowledge of brain functions will increase in the coming years , and consequently the observation scale may have to be revised after some time . now that the content validity has been described
internal consistency , interrater reliability , and intrarater reliability will be examined , as well as construct validity . for the latter
, results of the nosca will be related to clinical diagnoses , severity of dementia , and results of neuropsychological tests .
discriminant validity will be studied by comparing the results of the nosca with scores on depression .  
expecting positive results on the psychometric qualities , we are convinced that the implications of the nosca for the nursing practice will prove important .
furthermore , behavioural observation within a clinical environment provides invaluable information regarding underlying cognitive function .
the value of observation of daily behaviour for assessing cognitive functioning was the reason for miller et al . to develop the batch ( after we had finished our literature search ) .
this is an assessment tool to record observations of patients ' daily functioning under subheading that reflect cognitive domains .
they were interested in an observation scale for patients in a psychiatric setting ( mean age 50 years ) who refuse or can not undertake cognitive assessments .
the batch may well be interesting if more data are collected on validity , reliability , distinction between the subscale scores and if the scale were to be applied in a geriatric patient group . for geriatric patients , several methods for assessing their cognitive functioning need to be combined , and daily observation of cognitive functioning remains important because of its high ecological value .  
we expect that the nosca will be useful at hospital medical and surgical wards as well , because the items all cover behaviour which is easy to observe , and thus the scoring does not require specific geriatric expertise or knowledge . in other settings , such as home care and homes for the elderly , it will also be useful in assessing cognitive functioning . for these different settings , separate validation studies will be required .   for the time being , we recommend that nurses closely observe elderly patients and report cognitive functioning and dysfunctioning , and associated behaviour .
improving these systematic observations will enhance the ability of nurses to truly tailor their interventions to the patients ' abilities .
the nosca is a promising tool that will help nurses to perform the challenging observations of cognitive functioning , and thereby improve the quality of care provided to the fast growing number of older patients .
this research received no specific grant from any funding agency in public , commercial , or not - for - profit sectors .
 
 background . to assess a patient 's cognitive functioning is an important issue because nurses tailor their nursing interventions to the patient 's cognitive abilities . 
 although some observation scales exist concerning one or more cognitive domains , so far , no scale has been available which assesses cognitive functioning in a comprehensive way . 
  objectives . to develop an observation scale with an accepted level of content validity and which assesses elderly patients ' cognitive functioning in a comprehensive way . methods . 
 delphi technique , a multidisciplinary panel developed the scale by consensus through four delphi rounds ( > 70% agreement ) . 
 the international classification of functioning / icf was used as theoretical framework . results . 
 after the first two delphi rounds , the panel reached consensus about 8 cognitive domains and 17 sub domains . 
 after two other rounds , 39 items were selected , divided over 8 domains and 17 sub domains . 
 discussion . 
 the nurses ' observation scale cognitive abilities ( nosca ) was successfully designed . 
 the content validity of the scale is high because the scale sufficiently represents the concept of cognitive functioning : the experts reached a consensus of 70% or higher on all domains and items included ; and no domains or items were lacking . as a next step , the psychometric qualities of the nosca will have to be tested . 
1. Background
2. Objectives
3. Methods
4. Results
5. Conclusion
 Funding
 Conflict of Interests