The reliability and validity of the World Health Organization Disability Assessment Schedule (WHODAS-II) in stroke

Purpose: Psychometric properties of the World Health Organization Disability Assessment Schedule (WHODAS-II) in stroke have received some attention recently, mostly using classical approaches, but there is still an absence of investigation from a modern psychometric perspective. This study aimed to test the reliability and validity of the WHODAS-II in stroke, using modern psychometric analysis. Methods: A total of 188 community-dwelling poststroke patients were recruited. Internal construct validity was assessed by Rasch analysis, reliability by internal consistency and person separation index (PSI), and external construct validity by associations with Functional Independence Measure (FIM^?). Results: Rasch analysis indicated that total score (based upon 32 items, omitting the work-related items) was satisfactory, after adjustment for local dependency. The proposed “activities” and “participation” components also satisfied Rasch model expectations. An existing short form was problematic due to inclusion of a work-related item, but an alternative 10-item version was acceptable. Cronbach’s α for the WHODAS-II, its domains and components varied between 0.83 and 0.99 and PSI between 0.70 and 0.95. External construct validity was confirmed by expected correlations with FIM^?. Conclusions: WHODAS-II provides a reliable and valid instrument for measuring disability and components of “activities” and “participation” in stroke survivors. Various combinations of the item set may provide a range of scales to suit most research needs.

Implications for Rehabilitation

• The impact of stroke on patients’ functioning in terms of activities and participation is important in the postacute and long-term rehabilitation phase.

• The World Health Organization Disability Assessment Schedule (WHODAS-II) was developed specifically to measure activities and participation.

• Psychometric properties of the WHODAS-II in stroke have received some attention recently, mostly using classical approaches.

• This study has tested the reliability and validity of the WHODAS-II in stroke, using modern psychometric analysis and it has been found that WHODAS-II provides a reliable and valid instrument for measuring functioning and components of “activities” and “participation” in stroke survivors.

     

Stability and relative validity of the Multiple Sclerosis Impact Profile (MSIP)

Objective. To examine the stability and relative validity of the Multiple Sclerosis Impact Profile (MSIP) in criterion-related groups. The MSIP is a disease-targeted health impact measure based on a selection of International Classification of Functioning, Disability and Health (ICF) aspects selected by 98 patients and medical and non-medical health professionals.

Method. Data were obtained from a postal survey of 377 individuals with Multiple Sclerosis (MS) attending the MS centre of the University Medical Center Groningen (UH) and 153 subjects from the MS patients' association. Stability was tested with t-tests for paired samples and intraclass correlation coefficients for repeated measures in a sample of 251 individuals from the UH sample. The Relative Validity (RV) was estimated using the Short Form Questionnaire (SF-36), the World Health Organization Quality of Life-BREF (WHOQOL-BREF), the Disability and Impact Profile (DIP), the Impact on Autonomy Questionnaire (IPAQ) and the Groningen Activity Restriction Scale (GARS).

Results. These indicate that the MSIP is a stable measure in time. MSIP scales showed satisfactory and strong RV. In general, the domain-specific activities and participation measures (GARS and IPAQ) performed equally or slightly better than the comparable MSIP-scales, while the MSIP performed better than the multidimensional health impact measures (SF-36, DIP and WHOQOL-BREF).

Conclusion. The MSIP demonstrated good stability and RV compared to generic health impact and domain-specific measures.     

Dimensionality and scalability of the Motor Assessment Scale (MAS)

Purpose. The Motor Assessment Scale (MAS) has shown to be a reliable and valid instrument for measuring motor functioning for stroke patients. The purpose of this paper was to study dimensionality and scalability of the instrument.

Method. A total number of 137 patients were evaluated at admission and on discharge. To study dimensionality and scalability, Partial Credit Models (PCM) were applied for the eight items in the instrument and also for the upper limb and lower limb activities separately. Studies were performed to compare subgroups such as young/old, men/women and diagnosis to examine if the items had the same meaning for the subgroups.

Results. The items showed the same ordering for admission and discharge. Infit and outfit values varied between 0.5 and 1.9 at admission and 0.5 and 1.7 on discharge.

Conclusions. We conclude that the scalability of the different items is not optimal. For some items, the top and/or bottom levels are overrepresented and for other items the middle levels tend to cluster. There seems to be a single construct except for one of the items. The instrument also showed the same meaning for the different subgroups.     

Dimensionality and scalability of the Motor Assessment Scale (MAS)

Purpose. The Motor Assessment Scale (MAS) has shown to be a reliable and valid instrument for measuring motor functioning for stroke patients. The purpose of this paper was to study dimensionality and scalability of the instrument.

Method. A total number of 137 patients were evaluated at admission and on discharge. To study dimensionality and scalability, Partial Credit Models (PCM) were applied for the eight items in the instrument and also for the upper limb and lower limb activities separately. Studies were performed to compare subgroups such as young/old, men/women and diagnosis to examine if the items had the same meaning for the subgroups.

Results. The items showed the same ordering for admission and discharge. Infit and outfit values varied between 0.5 and 1.9 at admission and 0.5 and 1.7 on discharge.

Conclusions. We conclude that the scalability of the different items is not optimal. For some items, the top and/or bottom levels are overrepresented and for other items the middle levels tend to cluster. There seems to be a single construct except for one of the items. The instrument also showed the same meaning for the different subgroups.     

脑卒中机能障碍评定法运动项信度及效度研究

目的 :探讨脑卒中机能障碍评定法(SIAS_M)运动项的信度、效度。方法 :对1998年～1999年在中日友好医院康复部治疗的脑卒中患者77例进行运动功能检测。结果 :SIAS-M评定者信度、重测信度佳 (相关系数分别为0.919～0.986,0.916～0.989,P<0.001)(n=35);SIAS_M的内部一致性良好 ,Cronbacha系数为0.84(n=77);SIAS -M相应各项与FMA运动项 ,Brunstrom、Barthel指数、FIM步行项高度相关 (相关系数分别为0.914、0.701、0.704、0.702以上 ,P<0.001) (n=66);从散点图和经时变化中可知SIAS_M巧妙地集中了MMT、Brunstrom的优点 ,且比它们更敏感。结论 :SIAS_M具有良好的信度、效度 ,是一种可信、有效的评测脑卒中偏瘫运动功能的方法     

Construct validity of the stroke-specific quality of life questionnaire in ischemic stroke patients

Hsueh I-P, Jeng J-S, Lee Y, Sheu C-F, Hsieh C-L. Construct validity of the Stroke-Specific Quality of Life questionnaire in ischemic stroke patients.

Objectives

To investigate the construct validity of the commonly used 8- and 12-domain versions of the Stroke-Specific Quality of Life (SS-QOL) with a first-order factor model. The better-fitted version was further evaluated by a second-order factor structure model in order to determine whether a summary score is justified.

Design

Cohort study.

Setting

Outpatient stroke clinic.

Participants

Patients (N=388) with ischemic stroke.

Intervention

Not applicable.

Main Outcome Measures

The SS-QOL. We first conducted confirmatory factor analysis (CFA) to evaluate the construct validity of the first-order 8- or 12-domain versions of the SS-QOL. The better-fitted version was then validated by investigating the second-order health-related quality of life (HRQOL) factor.

Results

The 12-domain version, but not the 8-domain version, had sufficient goodness of fit (χ²=2041.7, df=1061, χ²/df=1.9, comparative fit index [CFI]=0.98, Tucker-Lewis index [TLI]=0.98, and root mean square error of approximation=0.05). All items of the 12-domain version showed acceptable factor loadings (>0.40) and were retained. Furthermore, the second-order CFA fit indices of the 12 domains were acceptable (χ²=2630.3, df=1115, χ²/df=2.4, CFI=0.97, TLI=0.97, root mean square error of approximation=0.06), indicating that a summary score was justified for representing the overall status of HRQOL.

Conclusions

Our results show that the construct validity of the 12-domain SS-QOL is well supported for measuring HRQOL in ischemic stroke patients. Thus, we recommend the 12-domain version of the SS-QOL for use in capturing the multiple impacts of stroke as well as overall HRQOL status on the basis of patients' perspectives.     

The Pediatric Version of the Eating Assessment Tool: a caregiver administered dyphagia-specific outcome instrument for children

Purpose: To develop and evaluate the psychometric properties of the Pediatric version of the caregiver administered Eating Assessment Tool.

Methods: The study included developmental phase and reported content, criterion validity, internal consistency and test–retest reliability of the Pediatric Eating Assessment Tool. Literature review and the original Eating Assessment Tool were used for line-item generation. Expert consensus assessed the items for content validity over two Delphi rounds. Fifty-one healthy children to obtain normative data and 138 children with cerebral palsy to evaluate test–retest reliability, internal consistency, and criterion validity were included. The Penetration-Aspiration Scale was used to assess criterion validity.

Results: All items were found to be necessary. Content validity index was 0.91. The mean score of Pediatric Eating Assessment Tool for healthy children and children with cerebral palsy was 0.26?±?1.83 and 19.5?±?11, respectively. The internal consistency was high with Cronbach’s alpha =0.87 for test and retest. An excellent correlation between the Pediatric Eating Assessment Tool and Penetration-Aspiration score for liquid and pudding swallowing was found (p?r?=?0.77; p?r?=?0.83, respectively). A score >4 demonstrated a sensitivity of 91.3% and specificity of 98.8% to predict penetration/aspiration.

Conclusions: The Pediatric Eating Assessment Tool was shown to be a valid and reliable tool to determine penetration/aspiration risk in children.

• Implications for rehabilitation

• The pediatric eating assessment tool: a new dyphagia-specific outcome survey for children.

• The Pediatric Version of the Eating Assessment Tool is a dysphagia specific, parent report outcome instrument to determine penetration/aspiration risk in children.

• The Pediatric Version of the Eating Assessment Tool has good internal consistency, test–retest reliability and criterion-based validity.

• The Pediatric Version of the Eating Assessment Tool may be utilized as a clinical instrument to assess the need for further instrumental evaluation of swallowing function in children.

     

Assessment of the measurement properties of quality of life questionnaires in Brazilian women with breast cancer

BACKGROUND:

There are several questionnaires available to assess quality of life in breast cancer, however the choice of the best questionnaire often does not take into account the adequacy of these questionnaires'' measurement properties.

OBJECTIVE:

To test the measurement properties of two generic quality of life questionnaires and one quality of life questionnaire specific for women with breast cancer.

METHOD:

We assessed 106 women after surgery for breast cancer. The assessment included application of the SF-36, WHOQOL-bref, and FACT-B+4 questionnaires as well as the Global Perceived Effect and Pain Numerical Rating scales. The participants were interviewed on three occasions to investigate internal consistency, floor and ceiling effects, construct validity, reproducibility, and responsiveness.

RESULTS:

Most of the instruments'' domains showed adequate internal consistency (Cronbach''s alpha varying from 0.66 to 0.91). Reliability varied from poor to substantial (ICC_2,1 between 0.39 and 0.87) and agreement varied from negative to very good. The SF-36 presented doubtful agreement and showed floor and ceiling effects in three domains. The domains of the generic questionnaires presented moderate to good correlation with the FACT-B+4 (Pearson varying from 0.31 to 0.69). The internal responsiveness varied from small to large (ES varying from -0.26 to 0.98) and external responsiveness was found in only some of the instruments'' domains.

CONCLUSIONS:

Most of the measurement properties tested for the WHOQOL-bref and FACT-B+4 were adequate as was their ability to assess quality of life in women with breast cancer. The SF-36 showed inadequacy in agreement and floor and ceiling effects and should not be used in women with breast cancer.     

Construct validity of the SF-12 in three different samples

Rationale, aims and objectives Studies have challenged the validity and underlying measurement model of the physical and mental component summary scores of the 36‐item Short‐Form Health Survey in, for example the elderly and people with neurological disorders. However, it is unclear to what extent these observations translate to physical and mental component summary scores derived from the 12‐item short form (SF‐12) of the 36‐item Short‐Form Health Survey. This study evaluated the construct validity of the SF‐12 in elderly people and people with Parkinson's disease (PD) and stroke. Methods SF‐12 data from a general elderly (aged 75+) population (n = 4278), people with PD (n = 159) and stroke survivors (n = 89) were analysed regarding data quality, reliability (coefficient alpha) and internal construct validity. The latter was assessed through item‐total correlations, exploratory and confirmatory factor analyses. Results Completeness of data was high (93–98.8%) and reliability was acceptable (0.78–0.85). Item‐total correlations argued against the suggested items‐to‐summary scores structure in all three samples. Exploratory factor analyses failed to support a two‐dimensional item structure among elderly and stroke survivors, and cross‐loadings of items were seen in all three samples. Confirmatory factor analyses showed lack of fit between empirical data and the proposed items‐to‐summary measures structure in all samples. Conclusions These observations challenge the validity and interpretability of SF‐12 scores among the elderly, people with PD and stroke survivors. The standard orthogonally weighted SF‐12 scoring algorithm is cautioned against. Instead, when the assumed two‐dimensional structure is supported in the data, oblique scoring algorithms appear preferable. Failure to consider basic scoring assumptions may yield misleading results.     

Validity and reliability of the Turkish translation of the Pediatric Evaluation of Disability Inventory (PEDI)

Purpose. To investigate the validity and reliability of the Turkish translation of the original Pediatric Evaluation of Disability Inventory (PEDI).

Method. On May 2003, we received permission from Boston University to translate and use the PEDI for Research purposes. PEDI Functional Skills scale and Caregiver Assistance scale was administered by physiatrists to 573 healthy Turkish children (295 males and 278 females; the age range: 7 months to 7½ years) in two different healthcare centres in Ankara. The Turkish translation of the PEDI was again administered to 102 children after five days in order to assess test-retest reliability. Intraclass correlation coefficients (ICC) and Cronbach's alphas (α) were calculated. The test-retest reliability was assessed by Spearman's correlation coefficient. Internal construct validity was assessed by using Rasch unidimensional measurement model.

Results. High Cronbach's α coefficients (≥0.98), high ICC values (≥0.96) and high Spearman correlation coefficients (≥0.86) were found. The internal construct validity was confirmed by good fit to the Rasch measurement model. The fit statistics conducted in the study was acceptable, except for some items.

Conclusions. The Turkish translation of the PEDI is valid and reliable for the Turkish child population. We believe that PEDI is a detailed and useful instrument for the evaluation of efficiency of pediatric rehabilitation programme.     

The validity,reliability, responsiveness and minimal clinically important difference of the de Morton mobility index in rehabilitation

Purpose: Determine the clinimetric properties of the de Morton Mobility Index (DEMMI) in an adult inpatient rehabilitation population.

Method: Prospective open cohort case series. DEMMI and functional independence measure assessed within three days of admission and discharge and seven-point Likert assessment of global change in mobility during inpatient rehabilitation reported by the patient, physical therapist and rehabilitation physician.

Results: A total of 366 patients had assessments of the DEMMI completed on both admission into and discharge from rehabilitation. There was no floor or ceiling effect observed in the sample, but there was a mild (19%) ceiling effect at discharge in patients with a stroke. Evidence was obtained for the convergent, discriminant and known group validity of the DEMMI. The minimal clinically important difference was obtained using two methods. The DEMMI was highly responsive to change (Cohen’s d?=?1.3).

Conclusions: The findings give support to the use of the DEMMI in rehabilitation patients and on the basis of previous studies, support the use of the DEMMI across the continuum of hospital settings.

• Implications for rehabilitation

• This study provides evidence that the clinimetric properties of the de Morton Mobility Index (DEMMI) are sound.

• The findings give support to the use of the DEMMI in rehabilitation patients.

• Our findings, in conjunction with previous research, support the use of the DEMMI across the continuum of hospital settings.

     

The QE Health Scale (QEHS): Assessment of the clinical reliability and validity of a spiritually based holistic health measure

Purpose.?To assess the clinical reliability and validity of a holistic health measure, the QE Health Scale (QEHS), for use with people with physical disabilities.

Method.?A test-retest design saw the QEHS administered and compared with established measures of health at admission and discharge from three-week inpatient rehabilitation programmes. Data was analysed by factor and correlation analysis. Clinician-reported credibility and usefulness of the theoretical basis of the QEHS, the QEHS itself, and Patient Profiles derived from the QEHS were also used to evaluate clinical validity.

Results.?The QEHS was judged to possess satisfactory reliability and validity.

Conclusion.?The QEHS is a clinically reliable, valid, credible and useful holistic health instrument to facilitate client-centred therapeutic interventions, inform decision-making and evaluate outcomes for people with physical disabilities.