Evaluation of the psychometric properties of the Stanford Health Assessment Questionnaire Disability Index (HAQ-DI) in people with Parkinson's disease.

The Stanford Health Assessment Questionnaire Disability Index (HAQ-DI) is a widely used patient-reported outcome for measuring functional disability during Activities of daily living (ADL) performance; Parkinson's Disease (PD) leads to alterations in body function, limited performance in ADLs and increased dependency, resulting in reduced quality of life. The aim of the present study was to analyzed the psychometric properties of HAQ-DI in a population with PD. People with diagnosis of PD were recruited for this study. The psychometric properties analyzed were internal consistency and construct validity using the Parkinson's Disease Questionnaire (PDQ-39) as gold standard. This study was conducted on 34 patients diagnosed with PD from February to October 2023. The internal consistency of the HAQ-DI was alpha=0.93. The study revealed significant correlations between the dimensions of the PDQ-39 and the subcategories of the HAQ-DI (0.03<r>0.91). Significant correlations also emerged between the demographic and clinical characteristics of participants and the subcategories of HAQ-DI. The HAQ -DI is a reliable and valid tool to assess ADLs in people with PD. This is the first study analyzing psy-chometric properties of this well-known assessment tool in a population with neurological disease, representing an important step to compare outcomes and ADLs independence in different populations.