What is the most appropriate way to analyse the WHODAS 2.0 score?

Abstract

BACKGROUND: The World Health Organization Disability Assessment Schedule (WHODAS 2.0) is a practical, generic and widely used tool to assess the functioning and disability in several settings and health conditions. Although the use of categorical variables is common, this choice to present data could separate persons with very close functioning profiles into different categories. PURPOSE: This study aims to compare different ways of expressing the WHODAS score and give elements for the researcher to understand and choose the most appropriate way to statistically analyse the WHODAS scores. METHODS: A methodological study with secondary data of one hundred ninety-five women. The WHODAS score was analysed in different ways and associated with sociodemographic characteristics, lifestyle, and health aspects. The Poisson regression was chosen with the final WHODAS score in four variations (continuous, dichotomous, polytomous, and quartiles), and the presence of chronic disease. RESULTS: The analysis showed statistical significance in the univariate analysis for the adjustment variables and all the variations of the disability variable. The distribution analysis of the prevalence ratio and the AIC evidenced that the WHODAS score as a continuous variable had the lower AIC and statistical significance, as well as the most significant area under the ROC curve. CONCLUSIONS: These results show that the use of the continuous variable is the most indicated and that the categorization of the WHODAS score should be avoided.