Federal University of Santa Catarina, Department of Physical Education, Campus Universitário Reitor João David Ferreira Lima, Brazil.
Federal University of Santa Catarina, Department of Physical Education, Campus Universitário Reitor João David Ferreira Lima, Brazil.
J Sci Med Sport. 2020 Mar;23(3):264-269. doi: 10.1016/j.jsams.2019.09.004. Epub 2019 Sep 13.
To investigate whether psychosocial variables mediate the effect of a multicomponent intervention on screen time reduction among Brazilian students from schools located in vulnerable areas.
A cluster-randomized controlled trial with a 4-month follow-up.
This study was conducted with 1085 students (548 in the intervention group and 537 in the control group), aged 11-17years. The intervention strategies focused on training teachers, increasing opportunities for physical activity at school, and reducing screen time, as well as health education. The questionnaire was administered before and after intervention with questions about the amount of time spent on TV and computer/video games on weekdays and weekend days (combined screen time). The potential psychosocial mediators (attitude, self-efficacy, family and school support) were measured through validated scales. Socioeconomic status was used as control variable. Multilevel mediation analyses were conducted using a product-of-coefficients test.
Psychosocial factors were not mediators of the effect of the intervention on screen time. The intervention significantly improved school support for both sexes (boys: 1.307; girls: 0.759; p<0.05) and older students (1.154; p<0.001). Attitude (boys: -0.228; 11-13years: -0.133; 14-17years: -0.152; p<0.05) and self-efficacy scales (boys: -0.040; girls: -0.104; 11-13years: -0.048; 14-17years: -0.100; p<0.05) were associated with reduced screen time.
The intervention produced a significant improvement of school support for both sexes, as well as older students. Enhancing attitude and self-efficacy may be a useful strategy for reducing screen time among boys and students of any age groups.
ClinicalTrials.Gov: NCT02439827. Registration date: May 3, 2015.
调查心理社会变量是否在多组分干预对巴西弱势地区学校学生减少屏幕时间的效果中起中介作用。
一项具有 4 个月随访的整群随机对照试验。
本研究纳入了 1085 名 11-17 岁的学生（干预组 548 人，对照组 537 人）。干预策略侧重于培训教师、增加学校体育活动机会和减少屏幕时间，以及健康教育。在干预前后通过问卷询问学生在工作日和周末每天看电视和电脑/视频游戏的时间（综合屏幕时间）。通过验证量表测量潜在的心理社会中介因素（态度、自我效能、家庭和学校支持）。社会经济地位被用作控制变量。使用乘积系数检验进行多层次中介分析。
心理社会因素不是干预对屏幕时间影响的中介因素。该干预显著改善了对所有性别（男生：1.307；女生：0.759；p<0.05）和年龄较大的学生（1.154；p<0.001）的学校支持。态度（男生：-0.228；11-13 岁：-0.133；14-17 岁：-0.152；p<0.05）和自我效能量表（男生：-0.040；女生：-0.104；11-13 岁：-0.048；14-17 岁：-0.100；p<0.05）与减少屏幕时间相关。
该干预对所有性别以及年龄较大的学生都显著改善了学校支持。增强态度和自我效能感可能是减少男生和任何年龄段学生屏幕时间的有效策略。
ClinicalTrials.Gov：NCT02439827。注册日期：2015 年 5 月 3 日。
