Evaluating the impact of World Health Organization ‘Nutrition-Friendly Schools Initiative’ approaches on adolescent nutrition outcomes in rural Sri Lanka

Background
Sri Lanka is a lower-middle income country (LMIC) currently experiencing a double burden of malnutrition. School-based approaches to promoting a healthy diet are one potentially promising method to address these public health challenges. The World Health Organization’s ‘Nutrition-Friendly Schools Initiative’ (NFSI) provides a framework of best practices for school-based approaches to promote healthy diets among students, but there has been a dearth of research assessing the impact of NFSI approaches on student nutrition outcomes.
Objectives
This thesis aims to describe the nutritional quality of the diets of adolescent students living in rural Sri Lanka, to identify if there was significant district- or school-level variation in the nutritional quality of these diets, and to see if there were significant associations between the schools’ NFSI approaches (summarised as the number of NFSI actions that schools were implementing) to promote healthy diets and student nutrition outcomes.
Methods
This study was part of a larger World Bank-funded project entitled ‘Integrating Nutrition Promotion and Rural Development.’ Data were collected in July-August 2014 and August- September 2015 from secondary school students (n=1300) and principals of schools (n=49) in three rural districts of Sri Lanka using clustered randomised sampling methods. Students’ demographics and diets were assessed using the WHO Global school-based student health survey (GSHS) and a validated food frequency questionnaire (FFQ). School actions to promoting healthy diets were collected using the ‘NFSI tool’ which was administered as a semi-structured interview with school staff. Diet quality was summarised using the Diet-Quality Index-International, BMI Z-scores, and intake of selected nutrients. Multilevel analyses were used to examine associations between school NFSI actions and student outcomes, while controlling for confounders at both the school- and student-levels.
Results
Results indicated that student’s diet quality was low, with notable deficiencies in protein and calcium. There was no significant between-district variation in student outcomes, but there was significant between-school variation, suggesting that there was a ‘school-effect’ on diet quality. However, multilevel analyses indicated that at both baseline and follow-up there were no significant associations between the number of NFSI actions that schools reported and student nutrition outcomes.
Conclusions
This study was, to the best of my knowledge, the first formal evaluation of NFSI actions and student outcomes. Further research is needed to examine associations between NFSI actions and student outcomes over a longer time-frame. Additionally, more work is needed to identify whether or not school variation in diet quality is due to school nutrition-promoting actions that are not currently included in the NFSI, actions that are not detected by the NFSI tool or other factors that are not measured in this study. In addition to conducting more research on the NFSI, further research is also needed to understand more generally the most effective school-based approaches to improve students’ diets.

Keywords: Health
Adolescent
Nutrition
Multilevel
Body Weight
School
Sri Lanka
World Health Organization
BMI
Advisor: Townsend, N
Rayner, M
Wickramasinghe, K