Wednesday, May 15, 2013

Breakfast

A few months ago, Social Service Providers Aotearoa asked me to review the literature on school breakfast programmes and provide an assessment of whether public funding of school breakfast programmes offered value for money. I spoke on the issue in Wellington and in Christchurch in February. As the government seems to be looking at the Mana Party's proposals around food in schools, it seems worth posting things here as summary.

I was only looking at school breakfast programmes, and so I can't here comment on school lunch programmes. I'm not sure why we'd expect results to vary greatly, but it's worth having the caveat.

Anyway, on my best read of the literature, it's hard to make a case for that we'd get any great benefit from the programmes. Rather, we often find that they don't even increase the odds that kids eat breakfast at all. Many shift breakfast from at-home to at-school, but among those who hadn't bothered with breakfast before the programme, not many wind up starting when schools provide it. You can then get kids reporting that they're less hungry as consequence of the programmes, but it's awfully hard to reject that the main thing going on is that kids are eating at 9 at school instead of at 7 at home and are consequently less hungry when asked at 11.

You can get some substantial results from school breakfast programmes in third world countries. But even there we need to watch for displacement effects: the benefit of the programmes is often the implicit income subsidy provided. In those cases, we can see evidence of families cutting back on food expenditures for the kid getting breakfast at school in favour of spending on the other kids; in the link provided, there's reasonable crowding out in a UK lunch programme. And if that's the benefit, cutting a cheque to the families instead just might be better.

In all the studies, I wish that there were a control group where the parents were just given cash equivalent to the per-student cost of putting on the programme. All of these kinds of programmes should be assessed against that kind of counterfactual to establish whether we're getting benefits from the programme, or from the implicit income transfer.

Here are a few typical pieces.

Devaney and Fraker, 1989, found that school breakfast programmes did not increase the likelihood of kids' eating breakfast at all. It did increase calcium intake and reduce consumption of cholesterol and iron - breakfasts provided at school differed from those they'd be getting at home.

Gleason, 1995, similarly found that school breakfast programmes did not influence the likelihood of students' eating breakfast.

Alderman and Bundy, 2011, concluded that food in schools isn't a great investment but could complement other investments - they focused on developing countries.

Bhattacharya, Currie and Haider, 2006, seems to be the touchstone for those advocating school breakfast programmes. They found improved nutritional outcomes in blood serum tests of kids participating in school breakfast programmes compared to the same kids during school holidays when they weren't getting the school breakfasts. But they also found no effect on the likelihood of eating breakfast. And I worry a bit about their identification strategy: because it's poorer schools who got school breakfast programmes, we might expect that there could be relevant differences in how parents respond to school holidays that might affect the difference between school/not school outcomes for reasons other than the programme.

Waehrer, 2008, in an unpublished study funded by the USDA's RIDGE programme, found that school breakfast participation reduced the likelihood of eating breakfast. We could imagine this happening where the kids don't really want breakfast anyway, the parents stop making them eat it at home because there's the programme at school, and then they skip it when they get to school. The study could have similar identification issues to the Bhattacharya piece noted above; they identify on weekday-weekend differences, but cohorts might respond differently to weekends.

Shemilt, Harvey, Shepstone et al, 2004, found pretty mixed outcomes in a messy randomised control trial. They wound up abandoning the RCT part of the analysis and just going for regressions. They found some evidence of worsened outcomes of having attended school breakfast programmes on a few behavioural measures, but I'm again not convinced that they've pinned down causality. What they seemed most sure of was that school breakfast programmes had kids eating more fruit, so I guess there's that.

There were a couple of pieces claiming reasonable benefits from school breakfast programmes too.

Powell, Walker, et al, 1998, ran a really nice randomised control trial in Jamaica. Kids in the programme got breakfast, those not in the programme were given a small piece of orange. So they're able to isolate socialisation effects from breakfast effects. They found that the treatment group saw small increases in nutritional status, achievement, and attendance; they suggested that "greater improvements may occur in more undernourished populations." I'm not convinced that we're in that category.

Murphy, Pagano et al (1998) found that moving from selective to universal school breakfast programmes had some benefits, but also had some odd results. Before intervention, "hungry and at-risk children were slightly, but not significantly, more likely to participate in the school breakfast program than nonhungry children", and that more than half of the hungry and at-risk kids rarely or never participated in voluntary school breakfast programmes. So stigma associated with voluntary programmes can substantially affect uptake. But, when the programmes were made universal, hungry and at-risk kids were only "somewhat more likely to increase their school breakfast participation than non-hungry children... although this difference was not statistically significant." So what do we then make of results showing some improved average outcomes at school but no particular increase in breakfast-eating among those who are hungry? I wonder if all the effects here point to that eating later in the morning rather than earlier is better. I'll talk more about this below.

Dotter, 2012, finds that universal in-class school breakfasts increase the number of children eating breakfast at school compared to voluntary programmes that could have stigma effects, but I couldn't see that the paper measured whether there was an effect on total breakfast consumption. And while Dotter finds increased school performance in schools with universal school breakfast programmes, I can't see how the paper distinguishes between an "eating at all" and an "eating later" effect. Why does this matter? Imagine an alternative policy where schools allow a designated morning tea break at 10:30 where kids bring in their own snacks. This would be cheaper than full school breakfast programmes and just as effective, if the main channel of effectiveness is having a fuller tummy at the time of instruction because breakfast was later.

Frisvold, 2012, found that state mandates requiring schools to provide school breakfast programmes increase availability of those programmes and consequently increase test scores: the paper reports math score increases of nine percent of a standard deviation and reading score increases of five percent of a standard deviation. Again, there is no significant effect on the total days per week that a student eats breakfast, suggesting substantial displacement of breakfasts that would otherwise have been eaten at home. The paper claims that the effect is through a nutrition channel, with kids eating healthier breakfasts. But I can't see how they're distinguishing the nutrition channel from my suggested "they're eating later in the morning and so are less hungry at 11" channel.

So, some bottom lines:

  • School breakfast programmes really don't seem to increase the likelihood of that kids eat breakfast at all;
  • To the extent that they improve outcomes in some studies, we really can't tell:
    • whether the effect is from changing the timing of breakfast, in which case we should instead have a morning tea break;
    • whether the effect is any better than just giving those families an equivalent cash transfer.
I spent an hour in Wellington and Christchurch walking through these findings. I hope we don't throw a pile of money at school breakfast programmes; the money could well be better spent. That also seemed to be the conclusion of a New Zealand study: Mhurchu et al, 2012, who found that the only effect of a randomised control trial of school free breakfast programmes here was that kids self-reported being less hungry.

Update: Lindsay Mitchell points to a presentation on the New Zealand trial. She also points to data showing child poverty rates have been dropping.

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