Psychometric properties of the Turkish version of the Parkinson’s disease quality of life-7 (PDQoL-7) in older adults

Parkinson’s disease (PD) is a common neurodegenerative condition in older adults and is associated with substantial impairment in quality of life. In geriatric populations, brief, and reliable disease-specific instruments are particularly important for reducing cognitive and physical burden during assessment. This study aimed to adapt the Parkinson’s Disease Quality of Life-7 (PDQoL-7) into Turkish and to evaluate its validity and reliability in older adults with PD. This methodological study included 129 individuals aged 65–90 years with PD who attended a neurology outpatient clinic between November 2023 and February 2025. The translation and cross-cultural adaptation process followed internationally accepted guidelines. Psychometric evaluation included internal consistency assessed by Cronbach’s alpha, test-retest reliability assessed using the intraclass correlation coefficient, construct validity examined through inter-item correlations and confirmatory factor analysis, and concurrent validity evaluated by correlations with the Parkinson’s Disease Questionnaire-39 (PDQ-39) and the Short Form-36 (SF-36). The Turkish PDQoL-7 demonstrated excellent test-retest reliability (ICC = 0.970; item ICCs = 0.863–0.947; p < 0.001) and internal consistency (Cronbach’s alpha = 0.928; item-deleted range: 0.913–0.921). Inter-item correlations (0.549–0.724) supported item homogeneity and a unidimensional structure. Confirmatory factor analysis confirmed a one-factor model with strong loadings (0.76–0.90) and good model fit (χ²(14) = 20.47, p = 0.116; CFI = 0.984; TLI = 0.977; RMSEA = 0.060; SRMR = 0.034). Strong correlations were found with PDQ-39 (r = 0.916) and SF-36 general health (r= -0.809). The Turkish version of the PDQoL-7 is a valid and reliable instrument for assessing quality of life in older adults with PD. Its brief structure and strong psychometric properties support its use in geriatric clinical practice and research settings. ClinicalTrials.gov, NCT06230926, registered on 19 January 2024.