Evaluation of the metric properties of the WHODAS 2.0, WHODAS-S, and RADS in the assessment of disability in Parkinsonian patients

• Published in: Clinical neurology and neurosurgery 2020-07, Vol.194, p.105872-105872, Article 105872
• Main Authors: Serrano-Dueñas, Marcos, Serrano, Maite, Mafla, Daniel, Martínez-Martín, Pablo
• Format: Article
• Language: English
• Subjects: 12-item WHO-DAS II; Activities of daily living; Basal ganglia; Central nervous system diseases; Cognitive ability; International Classification of Functioning, Disability and Health; Metric properties; Movement disorders; Neurodegenerative diseases; Neurological complications; Neurology; Parkinson's disease; Patients; Quality of life; Rapid Assessment of Disability Scale; Studies; Validity; World Health Organization Disability Assessment Schedule
• ISSN: 0303-8467; 1872-6968
• DOI: 10.1016/j.clineuro.2020.105872

•Out of 168 patients, 65.4% were men’s, 96 (57.1%) at stage III of Hoehn and Yahr. One hundred fifty-one patients lived independently in the community, 102 lived with their spouses, 108 were retired, and 48 were still working. Cronbach's alpha exceeded the minimum requirement of 0.70 for the three scales. The SEM obtained was, also for the three scales, higher than the ½ of the standard deviation value. The validity for known groups showed that all domains were significantly different in both WHODAS-S and RADS.•The stability of the scale was evaluated with the test-retest (ICC). The results for the WHODAS-2 ≤ 0.002; for the WHODAS-S were p ≤ 0.000]; and for the RADS were p ≤ 0.000].•Convergent validity analysis, showed that the three scales had a high correlation among them (0.62 to 0.63). The RADS correlated moderately to highly with all of the following: SCOPA-M, H&Y, CISI-PD, PIMS, HADS-A, HADS-D. In general, both formats of the WHODAS have adequate correlations with the PIMS, HADS-A, and HADS-D. All three scales had a weak correlation with years of illness•The RADS is by far the fastest scale to use. All three scales showed suitable metric properties Parkinson's disease is the second most prevalent progressive neurodegenerative disease and causes considerable disability in patients. We conducted a cross-sectional analytical study to examine the metric properties of the World Health Organization Disability Assessment Schedule 2.0 (WHODAS-2); the 12-item World Health Organization Disability Assessment Schedule (WHODAS-S) and the Rapid Assessment of Disability Scale (RADS) in assessing disability in Parkinsonian patients. Patients with cognitive impairment, neurological disorder, or disability due to any condition other than PD were excluded. One hundred sixty-eight consecutive patients were assessed in ON state. The following attributes were evaluated: data quality and acceptability, reliability, and construct (convergent and known-groups) validity. Testretest reliability was analyzed in fifty-six patients. Out of 168 patients, 65.4% were men's, 96 (57.1%) at stage III of Hoehn and Yahr. One hundred fifty-one patients lived independently in the community, 102 lived with their spouses, 108 were retired, and 48 were still working. Cronbach's alpha exceeded the minimum requirement of 0.70 for the three scales. The SEM obtained was, also for the three scales, higher than the ½ of the standard deviation value. The validity for known groups showed that all dom