Realist review to understand the efficacy of school feeding programmes

doi:10.1136/bmj.39359.525174.AD

BMJ 2007;335:858-861 (27 October), doi:10.1136/bmj.39359.525174.AD (published 22 October 2007)

analysis

Realist review to understand the efficacy of school feeding programmes

Trisha Greenhalgh, professor of primary health care¹, Elizabeth Kristjansson, associate professor², Vivian Robinson, doctoral candidate³

¹ Department of Primary Care and Population Sciences, University College London, London N19 5LW, ² School of Psychology and Institute of Population Health, University of Ottawa, Canada K1N 6N5, ³ Institute of Population Health, University of Ottawa

Correspondence to: T Greenhalgh p.greenhalgh@pcps.ucl.ac.uk

A recent Cochrane review found that school feeding programmessignificantly improve the growth and cognitive performance ofdisadvantaged children. Trisha Greenhalgh,Elizabeth Kristjansson,and Vivian Robinson look more closely at the highly heterogeneoustrials to see what works, for whom, and in what circumstances

The first 150 words of the full text of this article appear below.

Our Cochrane review of school feeding programmes in disadvantagedchildren included trials from five continents and spanned eightdecades.¹ Although we found that the programmes have significantpositive effects on growth and cognitive performance, the trialshad many different designs and were implemented in varying socialcontexts and educational systems; by staff with different backgrounds,skills, and cultural beliefs; and with huge variation in theprevailing social, economic, and political context. Simply knowingthat feeding programmes work is not enough for policymakersto decide on the type of intervention that should be implemented.We therefore looked at the trials more closely to determinethe aspects that determine success and failure in various situations.

Review methods

We analysed the 18 studies (reported in 29 articles) includedin our Cochrane review² ³ ⁴ ⁵ ⁶ ⁷ ⁸ ⁹ ¹⁰ ¹¹ ¹² ¹³ ¹⁴ ¹⁵ ¹⁶ ¹⁷¹⁸ ¹⁹ ²⁰ ²¹ ²² ²³ ²⁴ ²⁵ ²⁶ ²⁷ ²⁸ ²⁹ ³⁰ using the methods ofa realist review. Realist review exposes and articulates themechanisms by which the primary studies assumed the interventionsto . . . [Full text of this article]

Box 1 Process factors that seem to enhance efficacy of schoolfeeding programmes
Strong process evidence across many trials
Limited process evidence from one or few trials
Possiblefactors that might be tested in future studies
Box 2 Process factors that seem to reduce the efficacy of schoolfeeding programmes

Theories of why school feeding programmes work

Long term correction of nutritional deficiencies
Short term hunger relief
Children feel valued and looked after
Reduced absenteeism
Improved school diet inspires improved home diet
Improved literacy reduces intergenerational cycle of poverty

Theories why school feeding programmes do not work

Food offered is not consumed, or provides too little of the missing nutrient
Bioavailability
Compensatory reduction in food intake at other times
Supplementation occurs too late

Programme is not implemented as planned

Confounding or external variables

Discussion

Summary points

CiteULike

Complore

Connotea

Del.icio.us Add to Digg

Digg

Technorati What's this?

Make health inequality history: Trish Groves
BMJ 2007 335: 0. [Extract] [Full Text]

Framework for design and evaluation of complex interventions to improve health: Michelle Campbell, Ray Fitzpatrick, Andrew Haines, Ann Louise Kinmonth, Peter Sandercock, David Spiegelhalter, and Peter Tyrer
BMJ 2000 321: 694-696. [Extract] [Full Text] [PDF]

This article has been cited by other articles:

Stevens, D. P (2008). How do we know?. Qual Saf Health Care 17: 154-155 [Full text]
Brown, C, Hofer, T, Johal, A, Thomson, R, Nicholl, J, Franklin, B D, Lilford, R J (2008). An epistemology of patient safety research: a framework for study design and interpretation. Part 2. Study design. Qual Saf Health Care 17: 163-169 [Abstract] [Full text]