Giuseppe Magistrale1, Valerio Pisani1, Ornella Argento1, Chiara C Incerti1, Marco Bozzali2, Diego Cadavid3, Carlo Caltagirone4, Rossella Medori3, John DeLuca5, Ugo Nocentini6. 1. Neurology and NeuroRehabilitation Unit, Fondazione IRCCS Santa Lucia, Italy. 2. Neuroimaging Laboratory, Fondazione IRCCS Santa Lucia, Italy. 3. Neurology Clinical Development Group, Biogen Idec, USA. 4. Neurology and NeuroRehabilitation Unit, Fondazione IRCCS Santa Lucia, Italy/University of Rome "Tor Vergata", Italy. 5. Kessler Foundation, USA/Rutgers, New Jersey Medical School, USA. 6. Neurology and NeuroRehabilitation Unit, Fondazione IRCCS Santa Lucia, Italy/University of Rome "Tor Vergata", Italy u.nocentini@hsantalucia.it.
Abstract
BACKGROUND: The World Health Organization Disability Assessment Schedule (WHODAS-II) is a widely used generic assessment instrument for health and disability. However, a specific psychometric evaluation for this scale in multiple sclerosis (MS) is lacking. This study is aimed at the assessment of the psychometric properties of the WHODAS-II in MS with Cronbach's α and modern Rasch-model analyses. METHODS: The WHODAS-II was administered to 136 consecutively recruited MS patients. Several indexes of fit to the Rasch model were evaluated in order to assess internal construct validity. Internal consistency was assessed with Cronbach's α and the Person Separation Index (PSI). External validity was evaluated by analyzing correlations between the WHODAS-II and the Multiple Sclerosis Quality of Life-54 (MSQoL-54). RESULTS: Classical reliability indexes (Cronbach's α and intraclass correlation) showed good to excellent reliability for most of the subscales and for the total scale (α = 0.93). The total scale both with (36 items) or without (32 items) work items reached good fit to the Rasch model (PSI = 0.83). However, analysis of the subscales could resolve only four subscales out of seven. CONCLUSIONS: The WHODAS-II is a reliable and valid instrument for the assessment of patient-reported disability in MS, with some limitations including some item redundancy and questionable reliability of some subscales.
BACKGROUND: The World Health Organization Disability Assessment Schedule (WHODAS-II) is a widely used generic assessment instrument for health and disability. However, a specific psychometric evaluation for this scale in multiple sclerosis (MS) is lacking. This study is aimed at the assessment of the psychometric properties of the WHODAS-II in MS with Cronbach's α and modern Rasch-model analyses. METHODS: The WHODAS-II was administered to 136 consecutively recruited MSpatients. Several indexes of fit to the Rasch model were evaluated in order to assess internal construct validity. Internal consistency was assessed with Cronbach's α and the Person Separation Index (PSI). External validity was evaluated by analyzing correlations between the WHODAS-II and the Multiple Sclerosis Quality of Life-54 (MSQoL-54). RESULTS: Classical reliability indexes (Cronbach's α and intraclass correlation) showed good to excellent reliability for most of the subscales and for the total scale (α = 0.93). The total scale both with (36 items) or without (32 items) work items reached good fit to the Rasch model (PSI = 0.83). However, analysis of the subscales could resolve only four subscales out of seven. CONCLUSIONS: The WHODAS-II is a reliable and valid instrument for the assessment of patient-reported disability in MS, with some limitations including some item redundancy and questionable reliability of some subscales.
Authors: Ornella Argento; Chiara C Incerti; Maria E Quartuccio; Giuseppe Magistrale; Ada Francia; Carlo Caltagirone; Valerio Pisani; Ugo Nocentini Journal: Neurol Sci Date: 2018-04-27 Impact factor: 3.307
Authors: Giuseppe Magistrale; Rossella Medori; Diego Cadavid; Ornella Argento; Chiara Incerti; Valerio Pisani; Carlo Caltagirone; Marco Bozzali; John DeLuca; Ugo Nocentini Journal: Mult Scler J Exp Transl Clin Date: 2015-07-08
Authors: Alireza Akhbardeh; Jennifer K Arjona; Kristen M Krysko; Bardia Nourbakhsh; Pierre Antoine Gourraud; Jennifer S Graves Journal: Ann Clin Transl Neurol Date: 2020-02-26 Impact factor: 4.511
Authors: Lusine Vaganian; Sonja Bussmann; Maren Boecker; Michael Kusch; Hildegard Labouvie; Alexander L Gerlach; Jan C Cwik Journal: Qual Life Res Date: 2021-05-20 Impact factor: 4.147