J Prev Med Public Health.  2020 May;53(3):180-188. 10.3961/jpmph.19.324.

Verification of the Reliability and Validity of the Short Form 36 Scale in Indonesian Middle-aged and Older Adults

• Arovah NI
• Heesch KC

• KMID: 2503095
• DOI: http://doi.org/10.3961/jpmph.19.324

Abstract

Objectives
The Short Form 36 (SF-36) questionnaire is increasingly being used to measure health-related quality of life (HRQoL) in Indonesia. However, evidence that it is valid for use in Indonesian adults is lacking. This study assessed the validity and reliability of the SF-36 in Indonesian middle-aged and older adults.
Methods
Adults aged 46-81 years (n=206) in Yogyakarta, Indonesia completed the SF-36, another measure of HRQoL (the EuroQoL visual analogue scale [EQ-VAS]), and measures assessing their demographic characteristics. Fifty-four percent (n=121) completed the SF-36 measure again 1 week later. Confirmatory factor analysis was conducted to confirm the factor structure of the SF-36. Internal consistency reliability was estimated using Cronbach’s alpha, and test-retest reliability was assessed using intraclass correlations. Convergent and discriminant validity were assessed by computing correlations among SF-36 subscales, between subscales and the 2 component scores, and between component scores and EQ-VAS scores.
Results
Most scaling assumptions were met. The hypothetical factor structure fit the data poorly (root mean square error of approximation [RMSEA]=0.108) and modification was required for a good fit (RMSEA=0.060). Scores on all subscales demonstrated acceptable internal consistency (α>0.70) and test-retest reliability (r>0.70). Divergent validity was supported by weak to moderate interscale correlations (r=0.19 to 0.64). As expected, the 2 summary scores were moderately to strongly correlated with the EQ-VAS (r>0.60).
Conclusions
The findings adequately support the use of SF-36 in Indonesian middle-aged and older adults, although the optimal algorithm for computing component scores in Indonesia warrants further investigation.

Keyword

Quality of life; Survey and questionnaires; Reliability; Validity; Indonesia