RESUMEN
BACKGROUND: Huntington's disease is a progressive neurodegenerative disorder that usually manifests in adulthood and is inherited in an autosomal dominant manner. The main aim of the study was to assess the psychometric properties of the 12-item WHO Disability Assessment Schedule (WHODAS) 2.0 in studying the level of disability in people with Huntington's disease. METHOD: This is a cross-sectional study that covered 128 people with Huntington's disease living in Poland. We examined scale score reliability, internal consistency, convergent validity, and known-group validity. The disability and quality of life of people with Huntington's disease were also assessed. RESULTS: The scale score reliability of the entire tool for the research group was high. The Cronbach's α test result for the whole scale was 0.97. Cronbach's α for individual domains ranged from 0.95 to 0.79. Time consistency for the overall result was 0.99 and for particular domains ranged from 0.91 to 0.99, which confirmed that the scale was consistent over time. All of the 12-item WHODAS 2.0 domains negatively correlated with all of the Huntington Quality of Life Instrument (H-QoL-I) domains. All correlation coefficients were statistically significant at the level of p < 0.001. The results obtained in the linear regression model showed that with each subsequent point of decrease in BMI the level of disability increases by an average of 0.83 points on the 12-item WHODAS 2.0 scale. With each subsequent year of the disease, the level of disability increases by an average of 1.39 points. CONCLUSIONS: This is the first study assessing disability by means of the WHODAS 2.0 in the HD patient population in Poland, and it is also one of the few studies evaluating the validity of the WHODAS 2.0 scale in assessing the disability of people with HD in accordance with the recommendations of DSM-5 (R). We have confirmed that the 12-item WHODAS 2.0 is an effective tool for assessing disability and changes in functioning among people with Huntington's disease.
RESUMEN
PURPOSE: The purpose of this study was a cross-cultural adaptation of the Spine Functional Index to produce a Polish version (SFI-PL). Further, the psychometric properties were evaluated with standardized criteria patient reported outcome measures (PROMs) in a symptomatic Polish spine population. METHODS: Linguistic adaptation complied with the International Society for Pharmacoeconomics and Outcomes Research (ISPOR) guidelines to produce the SFI-PL. Subjects with spine conditions, all areas and multi-area, were recruited from a Polish Specialist Hospital (n = 225, age = 45.7 ± 16.0 years, range 18-87, female = 60%, symptoms duration = 13.93 ± 27.56 weeks, range 5-84). Baseline internal consistency, reliability and validity were examined and included the SFI-PL, Oswestry Disability Index (ODI), Neck Disability Index (NDI), EuroQol 5 Dimensions, 5-level version (EQ-5D-5L) and an 11-point pain Numerical Rating Scale (NRS) with retest at 3-7 days (= 5 days). Practicality for readability was considered within the face and content validity and completion and scoring time calculated. RESULTS: Statistical analysis showed excellent internal consistency (α = 0.90) and high test-retest reliability (ICC = 0.98). The error score was determined with the SEM = 3.14 (MDC 90% CI = 7.33%). The construct validity analysis demonstrated strong correlations between the SFI-PL, the NDI (r = 0.73) and the ODI (r = 0.82); moderate with the EQ index value (0.70) and EQ-VAS (r = 0.56). Time to complete (229 s) and score (27 s) were determined. CONCLUSIONS: The SFI-PL is a psychometrically sound PROM for Polish-speaking patients with spine conditions. The results support previous findings from the original-English and six other language versions for internal consistency, reliability, measurement error and validity. These slides can be retrieved under Electronic Supplementary Material.
