Effects of educational sessions on school backpack use among elementary school students

Objective: To evaluate the changes in loads carried, in the model of backpack used and in the way of carrying school backpacks after the implementation of an educational program. Methods: This study was performed on 99 children aged seven to 11 years at elementary school level in a private school in Sao Paulo, Sao Paulo, Brazil. The subjects' body mass (kg) and height (cm) and the loads carried in their backpacks (kg) were evaluated. The backpack models and the ways of carrying them were evaluated by filming before and after the intervention. The intervention program consisted of educational sessions offered to the children, parents and teachers. The sessions involved lectures about the spine and about the principles of load carrying. The children also received practical guidance relating to correct postures for load carrying. The children received monthly practical reinforcement for three months. The parents and teachers received reinforcement by means of information flyers and guidance on the school's home page. The data were analyzed by means of two-proportion equality and Wilcoxon statistical tests. The significance level was considered as alpha=0.05. Results: The use of a two-strap backpack model increased from 46.5% to 60.6% (p=0.046) and carrying it on two shoulders increased from 41.4% to 55.6% (p=0.047). The load carried in the backpacks decreased by 2.66kg (p 0.001) and the ratio between the subject's body mass and the load carried in the backpacks decreased by 7%. With regard to change per category, the number of subjects in the inappropriate group (load carried>15% of the subject's body mass) decreased (p<0.001). Conclusions: The educational sessions promoted changes in backpack use and it was observed a satisfactory adherence to the intervention program proposed. These results demonstrate the importance of Physical Therapy educational programs in schoolchildren's health. Article registered in the Clinical Trials. gov under the number NCT00536354.