Objective: 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.
Design: An evaluation of a school-wide intervention followed for two semesters.
Subjects: Two schools of similar size and demographic data were randomly assigned to either intervention or control. Participants were the children in these schools.
Intervention: 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.
Main outcome measures: Data were: (a) entree fat content (determined by a registered dietitian) and (b) the aggregate entree selections compiled from daily selection reports.
Statistical analyses performed: 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.
Results: 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.
Conclusions: 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.