Psychometric Evaluation of the Brunei-Malay SF-36 version 2 Health Survey

Abstract

Objectives: To culturally adapt the Short Form Health-36 version 2 (SF-36v2) into the Brunei-Malay context and<br />determine its reliability and validity for measuring health-related quality of life (HRQOL) in healthy individuals and<br />patients with chronic kidney disease in Brunei Darussalam. Methods: An iterative multistep strategy involving setting up<br />a bilingual expert panel, pretesting, text revision and back translation was used to prepare the Brunei-Malay SF-36v2 as<br />an adaptation from the Malaysian-Malay SF-36v2. The Brunei-Malay SF-36v2 was then self-administered to a sample of<br />healthy individuals (n=95) and predialysis chronic kidney disease outpatients (n=95) resident in Brunei. The mean<br />(SD) age of the participants was 46.6 (17.8) years. Results: Data completion rate was 100% with minimal floor effects<br />(≤0.21) in all the 8 domains and >15% ceiling effects in 3 of the 8 domain scales. Cronbach's alpha was >0.70 for all<br />the 8 domain scales. Scaling success was 100% for convergent validity, with 100% item discriminant validity for all<br />domain scales except Social Functioning (94%), Mental Health (85%) and General Health (85%). Principal component<br />analysis of the two-factor dimension explained 68% overall variance and accounted for 81% reliable variance, but the<br />exact SF-36 two-factor summary constructs in the standard algorithm were not replicated in the Bruneian population.<br />Conclusions: The Brunei-Malay SF-36v2 is a valid and reliable instrument for measuring HRQOL in healthy individuals<br />and patients with chronic kidney disease in Brunei. The summary scales should, however, be interpreted with caution.<br />Further studies should be carried out to assess additional psychometric properties of the Brunei-Malay SF-36v2.