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Published on: July 29, 2020
Exploring subgroup effects by socioeconomic position of three effective school-based dietary interventions: the
Nanna Lien1, Leen Haerens, Saskia J te Velde
1Department of Nutrition, Faculty of Medicine, University of Oslo, P.O. Box 1046, Blindern, 0316, Oslo, Norway, nanna.lien@medisin.uio.no.
Objectives:
The aim of this study was to explore subgroup effects by high and low socioeconomic position (SEP) of three previously conducted, effective European interventions.
Methods:
Reanalyses stratified by SEP were conducted by the research groups of each study. All studies were school-based: two multi-component interventions targeting intake of fat or fruit and vegetables (FV), and a free breakfast initiative.
Results:
Computer-tailored advice affected fat intake among low, but not high SEP girls after 1 year. A multi-component intervention affected the total FV intake in both SEP groups, vegetable intake in low SEP and fruit intake in high SEP across three countries after 1 year, whereas free fruit affected total FV and fruit intake equally in both SEP groups in one country after 2 years. Providing a free healthy breakfast increased consumption of healthy food items only in the low SEP group.
Conclusions:
Reanalysing intervention studies by SEP is a quick and easy way to explore patterns in effects by SEP across interventions. Providing healthy food might be a promising strategy for decreasing social inequalities.
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