Development and validation of a socioeconomic status short-form questionnaire (SES-SQ)

BACKGROUND: Evaluation of socioeconomic status (SES) is an important aspect in community-based health studies and it is a major predictor of health and nutritional status as well as mortality and morbidity from many diseases. This study aimed to construct and validate socioeconomic status short-from questionnaire (SES-SQ) in Iranian population. METHODS: This cross-sectional methodological study was conducted among 1437 Iranian general population. Face and content validity of the developed questionnaire was evaluated qualitatively. Internal consistency, construct validity using exploratory factor analysis (EFA) and latent class analysis (LCA), and convergent and known-group validity were also evaluated. RESULTS: The SES-SQ consisted of 6 items. The overall Cronbach’s alpha was 0.64, showing acceptable internal consistency. EFA resulted in two factors explaining 47.78% of total variance. Three SES classes (low/middle/high) were extracted by LCA. The score of SES-SQ ranged from 0 to 17; two cutoff scores of 4.5 and 8.5 were determined by receiver operating characteristic (ROC) analysis for differentiating low from middle and middle from high SES classes, respectively. CONCLUSION: An efficient, reliable, and valid short-form questionnaire was developed for evaluating SES in Iranian general population. The relevancy of questionnaire items is not lost over time.