Validation of the RAND 36-Item Health Survey questionnaire in Brazil

• Published in: Arquivos de gastroenterologia 2022-06, Vol.59 (2), p.193-197
• Main Authors: LINS-KUSTERER, Liliane, AGUIAR, Inácio, SANTOS-LINS, Larissa Souza, LINS-ROCHA, Matheus, AGUIAR, Carolina Villa Nova, MENEZES, Marta Silva, SAMPAIO, Aline Santos, QUARANTINI, Lucas C, COTRIM, Helma P, BRITES, Carlos
• Format: Article
• Language: English
• Subjects: GASTROENTEROLOGY & HEPATOLOGY
• ISSN: 0004-2803; 1678-4219; 1678-4219
• DOI: 10.1590/s0004-2803.202202000-36

ABSTRACT Background: Health-related quality of life is frequently used as an outcome measure that improves the quality of care. The SF-36 and RAND-36 were derived from the Medical Outcomes Study. Objective The present study aimed to validate the RAND-36 in Brazil, in healthy individuals and patients with liver disease. Methods: Confirmatory factor analysis (CFA) was conducted by using JASP Software. The parameters of the items were estimated using the Robust Diagonally Weighted Least Squares (RDWLS) approach. Comparative fit index (CFI), Goodness-of-fit index (GFI), Tucker-Lewis Index (TLI) and the root mean square error of approximation (RMSEA) were evaluated. Internal consistency was measured using the Composite reliability index. Convergent validity between RAND-36 domains and Work Ability Index (WAI) was conducted. Results: This validation study included 763 individuals, 400 (52.4%) with chronic liver disease. The most prevalent liver diseases were hepatitis C (13.9%), alcoholic liver disease (11.8%), and steatosis (12.1%). The measurement model tested using the CFA obtained the following adjustment indicators: X2 (df): 599.65 (498); CFI: 0.998; GFI: 0.998; TLI: 0.998; RMSEA: 0.016 (90%CI: 0.011-.021). Convergent validity of RAND-36 and total WAI ranged from medium to large correlation. Conclusion: The RAND-36 is effective in measuring the perception of health-related quality of life in individuals with and without chronic liver disease. The results of our study support the developer’s claims for the reliability of the RAND-36 version 1 as a measure of health-related quality of life. The evidence for the construct validity of the RAND-36 was substantial. RESUMO Contexto: A qualidade de vida relacionada à saúde é frequentemente usada como uma medida de resultado que melhora a qualidade da atenção à saúde. O SF-36 e o RAND-36 foram derivados do Medical Outcomes Study. Objetivo O presente estudo teve como objetivo validar o RAND-36 no Brasil, em indivíduos saudáveis e pacientes com doença hepática. Métodos: A análise fatorial confirmatória (AFC) foi realizada usando o software JASP. Os parâmetros do elemento foram estimados usando o método Robust Diagonally Weighted Least Squares (RDWLS). O índice de ajuste comparativo (CFI), o índice de adequação (GFI), o índice de Tucker-Lewis (TLI) e o erro quadrático médio de aproximação (RMSEA) foram avaliados. A consistência interna foi medida pelo índice de confiabilidade composta. A validade convergente foi realiz