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Beliz Acan Osman, Jonathan D Adachi, Tanveer Towheed, Wilma Hopman, K Shawn Davison and William D Leslie contributed equally to this work.
The authors declare that they have no competing interests
LML planned the study and analyses and drafted the manuscript. BAO conducted the analyses and drafted the manuscript. JA, TT, SD, WH, and WDL participated in planning the study and facilitating data access. All authors read and approved the final manuscript.
Studies that compare health-related quality of life (HRQOL) and other patient-reported outcomes in different populations rest on the assumption that the measure has equivalent psychometric properties across groups. This study examined the measurement equivalence (ME) of the 36-item Medical Outcomes Study Short Form Survey (SF-36), a widely-used measure of HRQOL, by sex and race in a population-based Canadian sample.
SF-36 data were from the Canadian Multicentre Osteoporosis Study, a prospective cohort study that randomly sampled adult men and women from nine sites across Canada. Confirmatory factor analysis (CFA) techniques were used to test hypotheses about four forms of ME, which are based on equality of the factor loadings, variances, covariances, and intercepts. Analyses were conducted for Caucasian and non-Caucasian females (n = 6,539) and males (n = 2,884). CFA results revealed that a measurement model with physical and mental health factors provided a good fit to the data. All forms of ME were satisfied for the study groups.
The results suggest that sex and race do not influence the conceptualization of a general measure of HRQOL in the Canadian population.