Paper Title
Low Back Pain among Students in Relation to the Weight of School Bag

Abstract
The association between the weight of school bag and Low Back Pain (LBP) amongst students remains under intense debate worldwide. This study aimed to estimate the prevalence of LBP amongst public high school students (14 to 19 years) in Kuwait and to investigate the association between LBP and the weight of school bag. A cross-sectional study using multistage cluster sampling with probability proportional to size method was conducted on a total of 950 public high school students from all governorates. Data on LBP were collected through face-to-face interviews using a standardized questionnaire. The students’ height and weight and the weight of their school bags were measured using appropriate weight and height scales. Logistic regression was used to investigate the association between the weight of school bags and LBP while adjusting for potential confounders. The estimated lifetime, 6-month, and 1-month prevalence of LBP were 70.3% (95% CI: 67.30– 73.21 %), 49.1% (95% CI: 45.83 – 52.28%), and 30.8% (95% CI: 27.81% – 33.78%) respectively, with significantly higher prevalence amongst females compared to males (p-value<0.001). The absolute weight of school bag was not significantly associated with LBP neither in univariate nor multivariate analysis. The relative weight of school bag (as a percentage of the body weight) was significantly associated with LBP in univariate analysis but not in multivariate analysis. The students’ perception towards their bag weight, however, was found to be significantly associated with LBP throughout the analysis (p-value<0.001). In conclusion, LBP amongst high school students in Kuwait seems to be very common with a prevalence resembling that of high-income countries. Our data suggest that the students’ perception on the weight of school bag is far more important than the actual weight. Current recommendations about the weight of school bags, which are not supported by evidence, should be revised to take into account the students’ perception on the weight of school bag. Keywords - Low Back Pain, Adolescents, school bags, Kuwait.