Measuring disability and function in older women: psychometric properties of the late-life function and disability instrument. Construction and international validation of CIVIQ-14 (a short form of CIVIQ-20), a new questionnaire with a stable factorial structure Development and validation of a muscular dystrophy-specific functional rating scale Psychometric properties of the Tinnitus Functional Index (TFI): Assessment in a UK research volunteer population Evaluation of the Irritable Bowel Syndrome Quality of Life (IBS-QOL) questionnaire in diarrheal-predominant irritable bowel syndrome patients Reliability and validity of shoulder function outcome measures in people with a proximal humeral fracture The Validity and Reproducibility of a Work Productivity and Activity Impairment Instrument Validation of the WHO Quality of Life assessment instrument (WHOQOL-100) in a population of Dutch adult psychiatric outpatients. Fear of Cancer Recurrence Inventory: development and initial validation of a multidimensional measure of fear of cancer recurrence Application of the multidimensional fatigue inventory (MFI-20) in cancer patients receiving radiotherapy. Development and validation of the European League Against Rheumatism response criteria for rheumatoid arthritis. Comparison with the preliminary American College of Rheumatology and the World Health Organization/International League Against Rheumatism Criteria. The Assessment of Quality of Life (AQoL) instrument: a psychometric measure of Health-Related Quality of Life Reliability and Validity of 6 Measures of Pain, Function, and Disability for Ankle Arthroplasty and Arthrodesis Development of a self-report screening instrument for assessing potential opioid medication misuse in chronic pain patients. The General Function Score: a useful tool for measurement of physical disability. Validity and reliability Validity of the Functional Gait Assessment in Patients With Parkinson Disease: Construct, Concurrent, and Predictive Validity Validity of the MACTAR questionnaire as a functional index in a rheumatoid arthritis clinical trial. The McMaster Toronto Arthritis. The ALSFRS-R: a revised ALS functional rating scale that incorporates assessments of respiratory function Establishing the minimal number of items for a responsive, valid, health-related quality of life instrument.
BACKGROUND The recent development of the Late-Life Function and Disability Instrument ( LL-FDI ) was an important contribution to the measurement of function and disability in older adults . The present study examined the psychometric properties and construct validity of the LL-FDI measure in a sample of older women . METHODS Older black ( n = 81 ) and white ( n = 168 ) women completed the LL-FDI  , several measures of physical function , and physical activity measures , and had their body mass index assessed at baseline of an ongoing prospect i ve study . Confirmatory factor analyses ( CFA ) and correlational analyses were used to examine factorial and construct validity of the measure . RESULTS The CFA , using an iterative model modification technique , result ed in an acceptable 15-item solution for the function component and an 8-item solution for the disability component . This abbreviated instrument demonstrated high correlations with the original scales . Construct validity for the LL-FDI was supported . Participants who demonstrated better physical function , reported being more active , and had lower body mass index reported less disability and less difficulty with function on the LL-FDI . CONCLUSIONS The LL-FDI appears to be an effective instrument for assessing function and disability in older women , and the abbreviated version reported here may prove useful in certain circumstances due to its brevity . However , continued determination of the construct validity of the complete and abbreviated scales is recommended Background The factorial instability of the CIVIQ-20 social dimension in different population s has necessitated the development of a new stable question naire to interpret results from international studies . Objective Construction of a stable and psychometrically vali date d question naire from CIVIQ-20 . Methods and major findings A prospect i ve , international study was used to construct a stable CIVIQ scale and to vali date its psychometric properties . An iterative process was implemented to eliminate the more unstable items ( six ) , and the social and physical dimensions were combined . The result ing instrument comprised 14 items , split into three dimensions ( pain , physical , and psychological ) , and was named CIVIQ-14 . The stability of the CIVIQ-14 factorial structure was confirmed in Polish , Czech , Spanish , and French population s using principal component analysis and multitrait/multi method analysis . Psychometric assessment demonstrated that CIVIQ-14 was reliable ( intra-class coefficient > 0.8 ; weighted kappa > 0.8 ) , valid ( correlation coefficients between dimension scores and clinical severity scores between 0.3 and 0.6 ) , and sensitive ( effect sizes > 0.6 for psychological dimension ; > 0.8 for the other dimensions ) . Conclusion CIVIQ-14 is a reliable , valid , and sensitive instrument applicable to international studies of patients with chronic venous disease Objective : To develop a reliable and valid new rating scale for measuring the functional impact of muscular dystrophy . Design : Prospect i ve and longitudinal investigation . Setting : Three academic medical centres in Taiwan and the Muscular Dystrophy Association of Taiwan . Measures : The Brooke Scale , the Vignos Scale , the Barthel Index , muscular strength , contracture severity , and predicted forced vital capacity ( FVC% ) . Methods : Scale development was in three stages . In stage I , a preliminary pool of 53 items was generated from patient interviews ( n-/25 ) , literature review , existing functional rating scales and expert opinion . In stage II , these items were administered to 85 patients with muscular dystrophy . The result ing data were analysed to construct a rating scale ( the Muscular Dystrophy Functional Rating Scale , MDFRS ) that encompassed four unidimensional constructs : mobility , basic activities of daily living , arm function and impairment . In stage III , the measurement properties of this rating scale were assessed in 121 muscular dystrophy patients different from those examined with the preliminary instrument . Results : Internal consistency reliability was excellent for all domains of the final 33-item scale , with values of Cronbach ’s alpha ranging from 0.84 to 0.97 . Intraclass correlation coefficients for test-retest and inter-rater reliability were 0.99 for all domains of the MDFRS . The MDFRS showed moderate to high correlations with a range of functional rating scales measuring similar aspects and impairment parameters ( Spearman ’s rho=0.65 - 0.91 ; P<0.001 , each ) . Confirmatory factor analysis supported a unitary construct of the four-dimensional MDFRS . The MDFRS had small floor and ceiling effects in the study sample s. Sensitivity to change was confirmed by large st and ardized response means for the MDFRS total score . Conclusions : The MDFRS is a reliable and valid disease-specific measure of functional status for patients with muscular dystrophy Objectives Question naires are essential for measuring tinnitus severity and intervention-related change but there is no st and ard instrument used routinely in research setting s. Most tinnitus question naires are optimised for measuring severity but not change . However , the Tinnitus Functional Index ( TFI ) cl aims to be optimised for both . It has not however been fully vali date d for research purpose s. Here we evaluate the relevant psychometric properties of the TFI , specifically the question naire factor structure , reproducibility , validity and responsiveness guided by quality criteria for the measurement properties of health-related question naires . Methods The study involved a retrospective analysis of data collected for 294 members of the general public who participated in a r and omised controlled trial of a novel tinnitus device ( Clinical Trials.gov Identifier : NCT01541969 ) . Participants completed up to eight commonly used assessment question naires including the TFI , Tinnitus H and icap Inventory ( THI ) , Tinnitus H and icap Question naire ( THQ ) , a Visual Analogue Scale of loudness ( VAS-Loudness ) , Percentage Annoyance question , the Beck 's Depression Inventory ( BDI ) , Beck 's Anxiety Inventory ( BAI ) , and the World Health Organisation Quality of Life-Bref ( WHOQOL-BREF ) . A series of analyses assessed the study objectives . Forty four participants completed the TFI at a second visit ( within 7–21 days and before receiving any intervention ) providing data for reproducibility assessment s. Results The 8-factor structure was not fully confirmed for this general ( non- clinical ) population . Whilst it was acceptable st and alone subscale , the ‘ auditory ’ factor showed poor loading with the higher order factor ‘ functional impact of tinnitus ’ . Reproducibility assessment s for the overall TFI indicate high internal consistency ( α = 0.80 ) and extremely high reliability ( ICC : 0.91 ) , whilst agreement was borderline acceptable ( 93 % ) . Construct validity was demonstrated by high correlations between scores on the TFI and THI ( r = 0.82 ) and THQ ( r = 0.82 ) , moderate correlations with VAS-L ( r = 0.46 ) , PR-A ( r = 0.58 ) , BDI ( r = 0.57 ) , BAI ( r = 0.39 ) and WHOQOL ( r = −0.48 ) . Floor effects were observed for more than 50 % of the items . A smallest detectable change score of 22.4 is proposed for the TFI global score . Conclusion Even though the proposed 8-factor structure was not fully confirmed for this population , the TFI appears to cover multiple symptom domains , and to measure the construct of tinnitus with an excellent reliability in distinguishing between patients . While the TFI may discriminate those whose tinnitus is not a problem , floor effects in many items means it is less appropriate as a measure of change in this subgroup . Further investigation is needed to determine whether these effects are relevant in other population Background Diarrhea-predominant irritable bowel syndrome ( IBS-d ) significantly diminishes the health-related quality of life ( HRQOL ) of patients . Psychological and social impacts are common with many IBS-d patients reporting comorbid depression , anxiety , decreased intimacy , and lost working days . The Irritable Bowel Syndrome Quality of Life ( IBS-QOL ) question naire is a 34-item instrument developed and vali date d for measurement of HRQOL in non-subtyped IBS patients . The current paper assesses this previously-vali date d instrument employing data collected from 754 patients who participated in a r and omized clinical trial of a novel treatment , eluxadoline , for IBS-d . Methods Psychometric methods common to HRQOL research were employed to evaluate the IBS-QOL . Many of the historical analyses of the IBS-QOL validations were used . Other techniques that extended the original methods were applied where more appropriate for the current data set . In IBS-d patients , we analyzed the items and substructure of the IBS-QOL via item reduction , factor structure , internal consistency , reproducibility , construct validity , and ability to detect change . Results This study supports the IBS-QOL as a psychometrically valid measure . Factor analyses suggested that IBS-specific QOL as measured by the IBS-QOL is a unidimensional construct . Construct validity was further buttressed by significant correlations between IBS-QOL total scores and related measures of IBS-d severity including the historically-relevant Irritable Bowel Syndrome Adequate Relief ( IBS-AR ) item and the FDA ’s Clinical Responder definition . The IBS-QOL also showed a significant ability to detect change as evidence d by analysis of treatment effects . A minority of the items , unrelated to the IBS-d , performed less well by the st and ards set by the original authors . Conclusions We established that the IBS-QOL total score is a psychometrically valid measure of  HRQOL  in IBS-d patients enrolled in this study . Our analyses suggest that the IBS-QOL items demonstrate very good construct validity and ability to detect changes due to treatment effects . Furthermore , our analyses suggest that the IBS-QOL items measure a univariate construct and we believe further modeling of the IBS-QOL from an item response theory ( IRT ) approach under both non-treatment and treatment conditions would greatly further our underst and ing as item-based methods could be used to develop a short form Abstract Purpose : Investigate test -- retest reliability and validity of five shoulder outcome measures in people during their active rehabilitation after a shoulder fracture . Method : This prospect i ve longitudinal study assessed shoulder function in 20 people ( 16 women , mean age 68.1 years ) with surgical or conservative management at 6 , 12 and 13 weeks post proximal humeral fracture using three patient-reported ( Disabilities of Arm , Shoulder and H and ; Oxford Shoulder Score ; Subjective Shoulder Value ) and two clinician-administered ( Constant Score ; UCLA Shoulder score ) outcome measures . Results : Content analysis categorised items into multiple domains of functioning for each outcome measure . Construct validity testing between measures found moderate to strong correlations ( r = 0.43–0.92 ) . Longitudinal validity ( responsiveness ) , represented by correlations between change scores , was moderate to strong ( r = 0.44–0.83 ) . Although ICCs2,1 for test – retest reliability ranged from 0.75 to 0.93 , Limits of Agreement between measurements were relatively wide ( 10–23 % of available range of scores ) . Minimal clinical ly important difference estimates varied between anchor- and distribution-based methods . Conclusions : The five outcome measures assessing shoulder function provided values for reliability and validity that meet measurement requirements for use in groups of people after a proximal humeral fracture . However , the use of these outcome measures might be limited by low absolute agreement between measurements and their content covering multiple domains of functioning . Implication s for Rehabilitation Linking the International Classification of Functioning , Disability and Health ( ICF ) to the content of common shoulder function outcome measures showed that multiple domains of functioning are combined into a single score . This might not be preferred for measurement of the single construct of “ shoulder function ” . Currently available shoulder function outcome measures may not be sufficiently reliable to monitor change in an individual after a proximal humeral fracture during the rehabilitation phase Summary The construct validity of a quantitative work productivity and activity impairment ( WPAI ) measure of health outcomes was tested for use in clinical trials , along with its reproducibility when administered by 2 different methods . 106 employed individuals affected by a health problem were r and omised to receive either 2 self-administered question naires ( self administration ) or one self-administered question naire followed by a telephone interview ( interviewer administration ) . Construct validity of the WPAI measures of time missed from work , impairment of work and regular activities due to overall health and symptoms , were assessed relative to measures of general health perceptions , role ( physical ) , role ( emotional ) , pain , symptom severity and global measures of work and interference with regular activity . Multivariate linear regression models were used to explain the variance in work productivity and regular activity by validation measures . Data generated by interviewer-administration of the WPAI had higher construct validity and fewer omissions than that obtained by self-administration of the instrument . All measures of work productivity and activity impairment were positively correlated with measures which had proven construct validity . These validation measures explained 54 to 64 % of variance ( p < 0.0001 ) in productivity and activity impairment variables of the WPAI . Overall work productivity ( health and symptom ) was significantly related to general health perceptions and the global measures of interference with regular activity . The self-administered question naire had adequate reproducibility but less construct validity than interviewer administration . Both administration methods of the WPAI warrant further evaluation as a measure of morbidity BACKGROUND Research concerning the psychometric properties of the  WHO Quality of Life Assessment Instrument ( WHOQOL-100 ) in general population s of psychiatric out patients has not been performed systematic ally . AIMS To examine the content validity , construct validity , and reliability of the WHOQOL-100 in a general population of Dutch adult psychiatric out patients . METHOD A total of 533 psychiatric out patients entered the study ( 438 r and omly selected , 85 internally referred ) . Participants completed self-administered question naires for measuring quality of life ( WHOQOL-100 ) , psychopathological symptoms ( SCL-90 ) , and perceived social support ( PSSS ) .  In addition , they underwent two semi-structured interviews in order to obtain Axis-I and Axis-II diagnoses , according to DSM-IV . RESULTS The drop-out percentage was low ( 7.1 % ) . Of the 24 facets of the WHOQOL-100 , 22 had a good distribution of scores , leaving out the facets physical environment and transport . Exploratory factor analysis revealed a four-factor structure , which was similar to earlier findings in patients with specific somatic diseases and depressive disorders . Various-a priori expected-positive and negative correlations were found between facets and domains of the WHOQOL-100 , and dimensions of the SCL-90 and the PSSS-score , indicating good construct validity of the WHOQOL-100 . The internal consistency of all facets and the four domains of the WHOQOL-100 was good ( Cronbach 's alpha 's ranging from 0.62 to 0.93 and 0.64 to 0.84 , respectively ) . Sparse and relatively low correlations were found between demographic characteristics ( age and sex ) and WHOQOL-100 scores . CONCLUSIONS Content validity , construct validity , and reliability of the WHOQOL-100 in a population of adult Dutch psychiatric out patients are good . The WHOQOL-100 appears to be a suitable instrument for measuring quality of life in adult psychiatric out patients Background Despite the fact that the fear of cancer recurrence is to varying degrees almost universal in cancer survivors , there is a lack of vali date d multidimensional instruments to evaluate this issue specifically . Purpose The goal of this study was to develop and empirically vali date a multidimensional self-report scale for assessing the fear of cancer recurrence , the  Fear of Cancer Recurrence Inventory ( FCRI ) . Methods A provincial medical data bank was used to r and omly select a pool of 1,704 French-Canadian patients who had been treated for breast , prostate , lung , and colorectal cancer within the past 10 years . Of these , 300 patients were asked to complete the FCRI on two occasions . Results The factorial analysis conducted on the final 42-item scale revealed a seven-component solution ( 64 % of the variance ) including the following factors : triggers , severity , psychological distress , coping strategies , functioning impairments , insight , and reassurance . The results also supported the internal consistency ( α = 0.95 ) and the temporal stability ( r = 0.89 ) of the FCRI , as well as its construct validity with other self-report scales assessing fear of cancer recurrence ( r = 0.68 to 0.77 ) or related constructs such as psychological distress ( r = 0.43 to 0.77 ) and quality of life ( r = −0.20 to −0.36 ) . Conclusions This study suggests that the French-Canadian version of the FCRI is a reliable and valid instrument for evaluating the multidimensional aspects of the fear of cancer recurrence In this paper the psychometric properties of the multidimensional fatigue inventory ( MFI-20 ) are established further in cancer patients . The MFI is a 20-item self-report instrument design ed to measure fatigue . It covers the following dimensions : general fatigue , physical fatigue , reduced activity , reduced motivation and mental fatigue . The instrument was used in a Dutch and Scottish sample of cancer patients receiving radiotherapy .  The dimensional structure was assessed using confirmatory factor analyses ( Lisrel 's unweighted least-squares method ) . The hypothesised five-factor model appeared to fit the data in both sample s ( adjusted goodness of fit ; AGFI : 0.97 and 0.98 ) . Internal consistency of the separate scales was good in both the Dutch and Scottish sample s with Cronbach 's alpha coefficients ranging from 0.79 to 0.93 . Construct validity was assessed by correlating the MFI-20 to activities of daily living , anxiety and depression . Significant relations were assumed . Convergent validity was investigated by correlating the MFI scales with a visual analogue scale measuring fatigue and with a fatigue-scale derived from the Rotterdam Symptom Checklist . Results support the validity of the MFI-20 . The highly similar results in the Dutch and Scottish sample suggest that the portrayal of fatigue using the MFI-20 is quite robust OBJECTIVE To vali date the European League Against Rheumatism ( EULAR ) , the American College of Rheumatology ( ACR ) , and the World Health Organization (WHO)/International League Against Rheumatism ( ILAR ) response criteria for rheumatoid arthritis ( RA ) . METHODS EULAR response criteria were developed combining change from baseline and level of disease activity attained during follow up . In a trial comparing hydroxychloroquine and sulfasalazine , we studied construct ( radiographic progression ) , criterion ( functional capacity ) , and discriminant validity . RESULTS EULAR response criteria had good construct , criterion , and discriminant validity , ACR and WHO/ILAR criteria showed only good criterion validity . CONCLUSION EULAR response criteria showed better construct and discriminant validity than did the ACR and the WHO/ILAR response criteria for RA This paper describes constructing the Assessment of Quality of Life ( AQoL ) instrument ; design ed to measure health-related quality of life ( HRQoL )  , and to be the descriptive system for a multi-attribute utility instrument . Unlike previous utility instruments ' descriptive systems , the AQoL 's has been developed using state-of-the-art psychometric procedures . The result is a descriptive system which emphasizes five different facets of HRQoL and which can cl aim to have construct validity . Based on the WHO 's definition of health a model of HRQoL was developed . Items were written by focus groups of doctors and the research ers . These were administered to a construction sample , comprising hospital patients , and community members chosen at r and om . Final construction was through an iterative process of factor and reliability analyses . The AQoL measures 5 dimensions : illness , independent living , social relationships , physical senses and psychological wellbeing . Each has three items . Exploratory factor analysis showed the dimensions were orthogonal , and each was unidimensional . Internal consistency was α = 0.81 . Structural equation modeling explored its internal structure ; the comparative fit index was 0.90 . These preliminary results indicate the AQoL has the prerequisite qualities for a psychometric HRQoL instrument for evaluation ; replication with a larger sample is needed to verify these findings . Scaling it for economic evaluation using utilities is being undertaken . Respondents have indicated the AQoL is easy to underst and and is quickly completed . Its initial properties suggest it may be widely applicable Background : Patient-reported outcome measures are increasingly used evaluating clinical care . Many measures used to assess operative hindfoot interventions vary in content , and some have not been psychometrically vali date d in this population . The purpose of this study was to compare measurement properties of  6 lower-extremity patient-reported outcome measures  , and to evaluate their reliability and validity in light of patients ’ preferences . Methods : Cross-sectional survey of 42 preoperative and 100 postoperative patients completed 6 lower-extremity outcome measures  on 2 occasions : Foot Function Index ( FFI ) , Ankle Osteoarthritis Scale ( AOS ) , patient-reported items of the  American  Orthopaedic Foot & Ankle Society Question naire ( AOFAS ) , Lower Extremity Functional Scale ( LEFS ) , Western Ontario and McMaster Universities Osteoarthritis Index ( WOMAC ) , and the Short Musculoskeletal Function Assessment ( SMFA ) , as well as measures of preference , and symptoms . Results : Internal consistency was good to excellent for all scales and subscales ( α = .84-.97 ; ICC [ 2,1 ] = .81-.96 ) . Correlations between scales ranged from .50 ( WOMACStiffness and FFIActivity Limitations ) to .92 ( LEFS and SMFAOverall , WOMACPain and AOSOverall , FFIOverall and AOFASOverall ) . Higher correlations occurred within instruments ( r = .97 AOSPain and AOSOverall ) and between similar subscales from different instruments ( r = .91 WOMACPain and AOSPain ) . Construct validity showed moderate to high correlations to global ratings of Pain , Stiffness , and difficulty performing Daily Activities . The highest correlations ( r > .75 ) occurred between Pain and AOSOverall ( r = .84 ) , stiffness and WOMACStiffness ( r = .81 ) , and Daily Activities and AOSDisability ( r = .87 ) . Patients rated instruments by preference . FFI , WOMAC , LEFS , and SMFA rated favorably for length . FFI , WOMAC , LEFS , and AOFAS rated high for underst and ability . FFI was rated by postoperative patients as most likely to capture change due to surgery . SMFA rated the best overall . Conclusions : Direct comparison of instruments revealed similarity between scales in construct validity and reliability . Patient preferences supported the use of these scales . Foot-specific instruments offered no clear advantage over lower-extremity instruments . Level of Evidence : Level II , prospect i ve comparative study This study constituted the first step in the psychometric development of a self-report screening instrument for risk of opioid medication misuse among chronic pain patients . A 26-item instrument , the Pain Medication Question naire ( PMQ ) , was constructed based on suspected behavioral correlates of opioid medication misuse , which heretofore have received limited empirical investigation . The PMQ  was administered to 184 patients at an interdisciplinary pain treatment center .  Reliability coefficients for the PMQ were found to be of moderate but acceptable strength . Construct and concurrent validity were examined through correlation of PMQ scores to measures of substance abuse , physical and psychological functioning , and physicians ' risk assessment s. To explore high and low cutoff points for misuse risk , subgroups were formed according to the upper and lower thirds of PMQ scores and compared on validity measures . Higher PMQ scores were associated with history of substance abuse , higher levels of psychosocial distress , and poorer functioning . Future psychometric analyses will consider predictive validity and examine shortened versions of the instrument Abstract The General Function Score ( GFS ) is a disease-specific instrument consisting of nine items focusing on strict physical activities of daily living . It is intended as an alternative to the more complex scores of disability ( such as the Oswestry Disability Index ) , serving as a complement to the quality of life instruments in the study of low back pain ( LBP ) . It was developed from an original 17-item question naire , of which 11 of the items were tested for criterion validity in an observer-supervised performance test . Two items were excluded from further analysis because of too low a validity . The remaining nine-item GFS was tested for construct validity , reliability , feasibility and responsiveness in six different cohorts : 297 patients with chronic low back pain ( cohort 1 ) , an age- and sex-matched control group of 287 r and omly allocated Swedish citizens ( cohort 2 ) , three separate groups of patients admitted for surgery due to low back disorders ( cohorts 3–5 ) and out patients with spinal disorders ( cohort 6 ) . Correlations were tested with the Spearman Rank correlation coefficient , differences between groups with the Mann-Whitney test and the internal consistency with the Cronbach 's coefficient α . The GFS total scores showed correlations of 0.78 , 0.81 and 0.88 in the three aspects of the performance test . The response rate was 98.3–100 % . The mean time to complete the question naire was 1.2 min . The internal consistency was 0.69 and 0.86 in cohorts 1 and 2 respectively . The test-retest correlation was 0.88 . The GFS showed a high responsiveness to difference and change . The effect size was 0.82–0.96 in surgically treated disc herniation and 0.55–0.85 in spondylolisthesis . The GFS is a highly valid and reliable instrument with good responsiveness and feasibility , useful for evaluation of physical disability Background The Functional Gait Assessment ( FGA ) is a vali date d measurement of gait-related activities in certain population s and may be potentially useful to assess balance and gait disorders in patients with Parkinson disease ( PD ) . Objective The purpose of this study was to determine the construct , concurrent , and predictive validity of the FGA in in patients with PD . Design This was a prospect i ve cohort study . Methods One hundred twenty-one in patients with PD were prospect ively enrolled . The FGA and other relevant appraisal s of gait , balance , disease severity , and activities of daily living were performed . Six months later , the patients were interviewed by telephone to have their fall information collected . Principal component analysis was used to determine construct validity . Spearman correlation coefficients were used to determine concurrent validity between the FGA and other measures . Cutoff point , sensitivity , specificity , and positive likelihood ratio were calculated for predictive validity based on the receiver operating characteristic curve . Results One common factor was extracted for construct validity , which cumulatively explained 64.0 % of the total variance . Correlation coefficients for the FGA compared with other measures ranged from .57 to .85 . The cutoff point for predicting falls was 18 , with sensitivity of 80.6 % , specificity of 80.0 % , and positive likelihood ratio of 4.03 . Limitations This study was limited by the length of time of follow-up and self-reports of falls without the requirement of a fall diary . Medication adjustment after the FGA evaluation may have led to a different cutoff score for identifying those patients who were at risk of falling . Conclusions The FGA demonstrated good construct validity in patients with PD . It had moderate to strong correlations with other balance and gait appraisal s. The FGA can be used to predict falls within the subsequent 6 months OBJECTIVES The McMaster Toronto Arthritis patient preference question naire ( MACTAR ) is a functional index that measures change in impaired activities selected by each patient in a baseline interview , and change in rheumatoid arthritis ( RA ) disease activity . In addition , it contains questions on the state of physical , social and emotional function and overall health , and their relation to RA . We evaluated MACTAR 's feasibility and validity ( content validity , construct validity , and responsiveness ) . METHODS A r and omized trial of combined treatment in 155 patients with early RA ; patients ' mean age at baseline was 50 years and median disease duration since diagnosis was 4 months . RESULTS Feasibility : MACTAR requires trained interviewers . In the trial , interviews took about 15 min . In longer term followup , activities selected at baseline may become less relevant as the pattern of disability changes . Followup from 153 patients ( 99 % ) was available . At least 5 impaired activities were identified and ranked by 147 patients ( 95 % ) ; interviewers could follow 99 % of these . The scoring system proved complex and required amendments . Content validity : Although its main focus is physical function , the MACTAR also contains generic questions ; 75 % of the patients named at least one impaired activity from the category " mobility . " Only 48 % were covered by Health Assessment Question naire ( HAQ ) items . Construct validity : MACTAR scores correlate highly with other functional indices and with measures of disease activity . Responsiveness : At 16 weeks the st and ardized response mean for the total MACTAR score in the combined-treatment group was excellent , at 2.2 . Items that directly address change were even more responsive . CONCLUSION The MACTAR interview is a valid and highly responsive instrument to assess change in functional ability of patients with early RA with active disease . It provides insight into problems -- mainly of physical function -- that really matter to patients . For st and ard clinical trials and clinical care , feasibility of the MACTAR is limited and the simpler HAQ remains the instrument of choice The ALS Functional Rating Scale ( ALSFRS ) is a vali date d rating instrument for monitoring the progression of disability in patients with amyotrophic lateral sclerosis ( ALS ) . One weakness of the ALSFRS as originally design ed was that it granted disproportionate weighting to limb and bulbar , as compared to respiratory , dysfunction . We have now vali date d a revised version of the ALSFRS , which incorporates additional assessment s of dyspnea , orthopnea , and the need for ventilatory support . The Revised ALSFRS ( ALSFRS-R ) retains the properties of the original scale and shows strong internal consistency and construct validity . ALSFRS-R scores correlate significantly with quality of life as measured by the Sickness Impact Profile , indicating that the quality of function is a strong determinant of quality of life in ALS Reducing the number of items in a health-related quality of life instrument will enhance efficiency . However , it is important to maintain measurement properties . We determined the effect of reducing items from each domain ( dyspnea , fatigue , emotion and mastery ) of the 20-item Chronic Respiratory Question naire ( CRQ ) .  Three r and omized trials of respiratory rehabilitation provided data . We removed items one at a time from each domain in three orders : by item impact , item responsiveness , and at r and om . Responsiveness , test-retest reliability and construct validity were evaluated at each step . Responsiveness and reliability , evaluated by intraclass correlation coefficients ( ICC ) , were reduced marginally as the number of items was reduced to two items per domain . The deterioration was greatest when reducing from two items to one . To detect a particular effect , sample size would increase by about 10 % when reducing the number of items in a domain to 2 . Construct validity showed a more marked deterioration . Reducing to two items per domain would maintain responsiveness and reliability of the CRQ at an acceptable level , with a trade-off of reduced construct validity and increase in sample size requirements
In general , estimates of construct validity were lower when vali date d against dissimilar constructs , except for instruments measuring impairments in mental functions .
CONCLUSION There is a trend that validation against a similar construct yields higher correlation coefficients than validation against a dissimilar construct .
PURPOSE This paper focuses on the construct validity of instruments measuring impairments in body structures and function in rheumatic disorders .
The objective is : 1 ) to make an inventory of constructs , based on the domains of the International Classification of Functioning , Disabilities and Health problems ( ICF ) , against which instruments measuring impairments in body structures and function were vali date d ; 2 ) to analyse whether validation against a similar construct result ed in higher correlation coefficients than validation against a dissimilar construct .