Bartholomew John B, Jowers Esbelle M
Department of Kinesiology and Health Education, University of Texas at Austin, 78712-1204, USA.
J Am Diet Assoc. 2006 Feb;106(2):248-52. doi: 10.1016/j.jada.2005.10.030.
A two-phase study was conducted to determine the effect of an environmental intervention aimed to increase the selection of low- and moderate-fat entrees at school.
An evaluation of a school-wide intervention followed for two semesters.
Two schools of similar size and demographic data were randomly assigned to either intervention or control. Participants were the children in these schools.
In Phase 1, the rotation of existing entrees was modified such that one of three entree choices was low or moderate in fat. In Phase 2, the number of competing high-fat entrees was reduced from two choices to one.
Data were: (a) entree fat content (determined by a registered dietitian) and (b) the aggregate entree selections compiled from daily selection reports.
Frequency distributions were used to describe entree availability. Two-way analysis of variance indicated differences in the mean daily selection of low-, moderate-, and high-fat entrees.
In Phase 1 in the intervention school, the number of days that a low-fat entree was offered increased by 70%, with no increase in the rate of selection of the low- or moderate-fat entrees. In Phase 2, both low- and moderate-fat entrees were selected at a higher rate in the intervention school (32.1% and 26.4%, respectively) than the control school (13.8% and 7.5%, respectively), P<0.01.
Increasing the availability of low- and moderate-fat entrees is not sufficient to increase their rate of selection. However, their rate of selection is increased as the availability of high-fat entree choices is reduced.
开展一项两阶段研究，以确定一项环境干预措施对增加学校低脂肪和中等脂肪主菜选择的效果。
对一项全校范围的干预措施进行为期两个学期的评估。
两所规模和人口数据相似的学校被随机分配到干预组或对照组。参与者为这些学校的儿童。
在第一阶段，调整现有主菜的轮换方式，使三种主菜选择之一为低脂肪或中等脂肪。在第二阶段，将竞争性高脂肪主菜的选择数量从两种减少到一种。
数据包括：（a）主菜脂肪含量（由注册营养师确定）和（b）从每日选择报告中汇总的主菜选择情况。
使用频率分布来描述主菜供应情况。双向方差分析表明低脂肪、中等脂肪和高脂肪主菜的每日平均选择存在差异。
在干预学校的第一阶段，提供低脂肪主菜的天数增加了70%，但低脂肪或中等脂肪主菜的选择率没有增加。在第二阶段，干预学校中低脂肪和中等脂肪主菜的选择率（分别为32.1%和26.4%）均高于对照学校（分别为13.8%和7.5%），P<0.01。
增加低脂肪和中等脂肪主菜的供应不足以提高其选择率。然而，随着高脂肪主菜选择的减少，它们的选择率会增加。
