Socioeconomic Inequalities in Quality of Life in Iranian Children and Adolescents: The Weight Disorder Survey of the CASPIAN-IV Study

Background: We aimed to determine the association between socioeconomic status (SES) and health-related quality of life (HRQOL) in a representative sample of Iranian children and adolescents. Study design: A cross-sectional study. Methods: In this nationwide school-based study, 6-18-yr-old students were selected via multistage cluster random sampling method from 30 provinces of Iran in 2011-2012. SES of each participant was determined using the categories of the Progress International Reading Literacy Study (PIRLS) for Iran and the Principle Component Analysis (PCA) method. The students’ HRQL was evaluated using the Persian version of the Pediatric Quality of Life Inventory (PedsQL™ 4.0TM 4.0) Generic Core Scales. The level of physical activity was evaluated using the physical activity questionnaire for adolescents. The association between SES and HRQL was evaluated using multiple linear regression analysis. Results: Overall, 23043 students were enrolled. The mean of total PedsQL™ score, school function, and psychosocial subscales was significantly different between different categories of SES (P<0.001). The differences in total population and among girls were between low and middle categories and low and high categories, but in boys, the difference was between low and high categories. There was a significant association between SES and school functioning, psychosocial function, and total score of HRQOL. Moderate and high SES had higher score compared to low SES group [β=1.0(0.5-1.6) for Moderate SES/Low SES and β=1.6(1.0-2.2) for High SES/Low SES]. Conclusion: SES is in positive association with HRQOL of Iranian schoolchildren, mainly due to its impact on school function. HRQOL could be improved by elimination of the socio-economic inequalities especially in the field of school function.