Ergonomic factors of school bags and their adaptation to the weight of students

BACKGROUND

Students use a school bag to carry their school supplies which may not have the required standards and ergonomic factors.

OBJECTIVE

This study was aimed to examine the ergonomic factors of schoolbags and their adaptation to the weight of elementary school students.

METHODS

This cross-sectional study was carried out on 721 primary schoolchildren. To collecting data a checklist, which its final version was approved by the experts, was designed by researchers. Data were analyzed by using SPSS ver. 22 and Chi-square test, One-Way ANOVA, and univariate and multivariate logistic regression models.

RESULTS

In this study, about 90.1% of students used a backpack to carry their items and most students carried backpacks with a weight up to 10% of their body weight. In 43.5% of the students, waist width was appropriate with backpack width at the bottom, and in 96.6% shoulder width was appropriate with backpack width at the top. Multivariate logistic regression showed that girls in compared to boys were more likely tolerated ratio of backpack weight to body weight, and also had more likely proportion of waist width and the backpack width at the bottom. The grades of the first, second, and fourth used more heavy backpacks. Students who their mothers were employee compared to housewives, carried heavier backpacks and had more likely proportion of waist width and the backpack width at the bottom. As the mother's age increased, the proportion of waist width and the backpack width at the bottom is diminished.

CONCLUSION

The schoolbags weight of many students was more than the standard weight, and their schoolbags did not have the required standards. Educational interventions can increase the knowledge of students and parents about the ideal weight of a schoolbag and the criteria for choosing a proper school bag.

Development and validation of the tool for the evaluation of the behavioral factors affecting the prevalence of musculoskeletal disorders in Iranian students

Background

This study was conducted with the aim of developing a standard and valid questionnaire to evaluate the behavioral factors affecting musculoskeletal disorders among adolescent students based on the educational and ecological diagnosis phase of the PRECEDE model.

Methods

Based on the PRECEDE model and by using available resources and a panel of experts, a reservoir of items was proposed. The content validity of the questions was measured using content validity ratio (CVR) and content validity index (CVI). 400 Iranian first-year female high school students completed the questionnaire. The construct validity was assessed using confirmatory factor analysis (CFA). The reliability of the questionnaire was evaluated using Cronbach’s alpha coefficient.

Results

The age range of study students was 13.69 ± 0.86 years. The final developed questionnaire included 25 items in three dimensions: knowledge (9 items), attitude (10 items) and enabling factors (6 items). The mean scores of CVI and CVR were 0.97 and 0.92, respectively. The results of CFA confirmed the three-factor structure of the questionnaire. The Cronbach’s alpha coefficients of the dimensions of knowledge, attitude and enabling factors were 0.65, 0.80 and 0.71, respectively.

Conclusions

The present questionnaire had appropriate psychometric properties and could be used as a valid tool in evaluating the factors affecting the development of musculoskeletal disorders among adolescent students.