Validation of the Short-Form 36 Health Survey (SF-36) for use in Mexican older persons

The Short Form 36 (SF-36) Health Survey has been widely used and has proven to be a valid and reliable scale for assessing health-related quality of life (HRQoL). However, research on HRQoL and validation of measurement scales in Mexico for its use with older persons is still incipient. The objective of this study was to evaluate the psychometric properties of SF-36 in a sample of 1,915 community-dwelling Mexicans 60 years and older, from two Mexican cities. Item mean scores were lowest in the dimensions of General Health (58.6), Social Functioning (58.9) Role Physical (66.5) and Vitality (67.8), and the highest mean scores were obtained in the Role Emotional (82.2), Mental Health (76.9), Bodily Pain (72.2) and Physical Functioning (70.3). The SF-36 showed appropriate internal consistency, construct validity, and factor structure. Reliability results showed a Cronbach's alpha with coefficient for all subscales between 0.79 and 0.87 indicating good reliability. Exploratory factor analysis showed six factors, different from its original structure. The Social functioning subscale presented the least acceptable results, which may reflect different understandings in the Mexican older population. The SF-36 showed good discrimination between groups of individuals with and without chronic diseases, and high correlation between depressive symptoms, economic situation, and social support. Results show that the SF-36 is adequate for use in Mexican older persons. In future studies, health outcomes for this population group in Mexico may be consistently assessed using the SF-36.