Reliability and Validity of 39-Item Parkinson’s Disease Questionnaire and Parkinson’s Disease Quality of Life Questionnaire

• Autor(a) principal: Jesus-Ribeiro, Joana
• Data de Publicação: 2017
• Outros Autores: Vieira, Elsa, Ferreira, Pedro, Januário, Cristina, Freire, António
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: https://www.actamedicaportuguesa.com/revista/index.php/amp/article/view/8202
• topic: Parkinson Disease; Quality of Life; Surveys and Questionnaires; Doença de Parkinson; Inquéritos e Questionários; Qualidade de Vida

Introduction: Parkinson’s disease has a significant impact in quality of life, which can be assessed with 39-item Parkinson’s Disease Questionnaire and Parkinson’s Disease Quality of Life Questionnaire. This study aimed to evaluate the reliability and validity of these scales in Portuguese patients.Material and Methods: Reliability was assessed through internal consistency (Cronbach’s alpha) and reproducibility (intraclass correlation coefficient). Regarding construct validity, we performed one-way analysis of variance across different groups according to modified Hoehn and Yahr scale. For criterion validity, we compared both scales with each other and with the Short Form 36-item Health Survey.Results: In a total of 100 patients with Parkinson’s disease, Cronbach’s alpha ranged for 39-item Parkinson’s Disease Questionnaire between 0.66 - 0.98, and for Parkinson’s Disease Quality of Life Questionnaire, between 0.78 - 0.98. Intraclass correlation coefficient for 39-item Parkinson’s Disease Questionnaire ranged between 0.49 - 0.96, and for Parkinson’s Disease Quality of Life Questionnaire, ranged between 0.65 - 0.96. Both scales showed, in general, capacity to discriminate differences among patients in the different stages of disease. The scales presented moderate to strong magnitude correlations with some Short Form 36-item Health Survey domains.Discussion: Cronbach’s alpha coefficients for most domains were satisfactory. Overall, it has been demonstrated good reproducibility, as well as construct and criterion validity.Conclusion: The Portuguese versions of both scales showed to be valid and reliable.