The psychometric properties of the Chinese version of the SF-36 health survey in patients with myocardial infarction in mainland China

Objective: To test the reliability and validity of the Chinese Mandarin version of the SF-36 health survey (CM:SF-36) in patients with myocardial infarction (MI) in mainland China. Methods: Single group, cross-sectional design to test the measurement performance on a convenience sample of 180 Chinese patients with MI, 30 of whom were retested after 2 weeks to establish reliability. Findings: Cronbach's α coefficients exceeded the 0.70 criterion for all subscales except General Health, indicating good internal consistency. Test-retest reliability was adequate (intraclass correlation coefficient >0.70) for all subscales. The significant differences were detected by the presence or absence of co-morbidities and the number of risk factors in most physical subscales indicating good discriminative validity. Principal components factor analysis with varimax rotation confirmed the presence of the eight factors, though the item loadings of the Vitality and Mental Health subscales were found to differ from the original ones of the SF-36. Conclusion: The CM:SF-36 is a psychometrically acceptable instrument for assessing the health status of Chinese patients with myocardial infarction.