Division of Community Health Sciences, UC Berkeley School of Public Health, Berkeley, CA, USA.
Nutrition Policy Institute, UC Agriculture and Natural Resources, Berkeley, CA, USA.
Child Obes. 2020 Aug;16(S1):S14-S22. doi: 10.1089/chi.2019.0233. Epub 2020 Mar 10.
Schools meals offer a critical opportunity for improving youths' diets, particularly for economically disadvantaged students. We examine the impact of a multipronged intervention to increase middle and high school students' lunch participation in an urban school district. In school years 2015-2016 through 2017-2018, a quasi-experimental study was conducted in 24 secondary schools, half ( = 12) of which received the following intervention: cafeteria redesign, additional school lunch points-of-sale (mobile carts and vending machines), and teacher education. From baseline to follow-up, lunch participation dropped 4.1% in intervention and 5.1% in comparison schools (difference-in-difference 1.0%, 95% CI 0.5-1.4). The overall decline in lunch participation occurred simultaneously with a drop-in free or reduced-price meal eligibility (from 72% to 58%) across all schools, which is likely related to changing local economic conditions, including a county-wide minimum wage increase that began in summer 2015. Among students eligible for free or reduced-price meals, participation decreased 1.8% in intervention and 4.9% in comparison schools (difference-in-difference 3.1%, 95% CI: 2.5-3.7), with a larger difference-in-difference seen in high schools (5.0%, 95% CI: 4.2-5.9) than middle schools (1.8%, 95% CI: 0.8-2.6). While this intervention demonstrated a modest, but significant relative increase in school lunch participation, the effect was not sufficient to halt large district-wide declines in participation during this study period. Given the significant time, money, and political capital required to implement the intervention, districts should carefully consider similar investments. Broader public policies or other changes to economic conditions that affect eligibility for means-tested benefits-in this case, a strengthening local economy coupled with an increased local minimum wage-may influence school lunch participation more than school-level interventions.
学校餐食为改善青少年饮食提供了一个关键机会，尤其是对经济困难的学生而言。我们研究了一项多管齐下的干预措施对提高城市学区中学生午餐参与度的影响。在 2015-2016 学年至 2017-2018 学年期间，在 24 所中学中进行了一项准实验研究，其中一半（ = 12）学校接受了以下干预措施：自助餐厅重新设计、增加学校午餐销售点（流动推车和自动售货机）以及教师教育。从基线到随访，干预组的午餐参与率下降了 4.1%，对照组下降了 5.1%（差异为 1.0%，95%置信区间为 0.5-1.4）。所有学校的免费或降价餐资格都同时下降（从 72%降至 58%），这可能与当地经济状况的变化有关，包括 2015 年夏季开始的全县最低工资上涨。在有资格享受免费或降价餐的学生中，干预组的参与率下降了 1.8%，对照组下降了 4.9%（差异为 3.1%，95%置信区间：2.5-3.7），其中高中的差异更大（5.0%，95%置信区间：4.2-5.9），初中（1.8%，95%置信区间：0.8-2.6）。尽管这项干预措施显示了学校午餐参与度的适度但显著的相对增加，但在本研究期间，这一效果不足以阻止参与率的大幅下降。鉴于实施干预措施需要大量的时间、资金和政治资本，各地区应仔细考虑类似的投资。更广泛的公共政策或其他影响经济条件的变化，会影响到经济状况调查福利的资格——在这种情况下，本地经济的增强加上当地最低工资的提高——可能会比学校层面的干预更能影响学校午餐的参与度。
