October 14, 2012

One of the most important meals of the day

Stuff is reporting “Food and learning connection shot down”,based on a local study

Researchers at Auckland University’s School of Population Health studied 423 children at decile one to four schools in Auckland, Waikato and Wellington for the 2010 school year.

They were given a free daily breakfast – Weet-Bix, bread with honey, jam or Marmite, and Milo – by either the Red Cross or a private sector provider.

My first reaction on reading this was: why didn’t they take this opportunity to do a randomised trial, so we could actually get reliable data.  So I went to the Cochrane Library to see what randomised trials had been done in the past. These have mostly been in developing countries and have found improvements in growth, but smaller differences in school performance.

Then I tried asking the Google, and its second link was a paper by Dr Ni Mhurchu, the researcher mentioned in the story, detailing the plans for a randomised trial of school breakfasts in Auckland.  At that point it was easy to find the results, and see that in fact Stuff is talking about a randomized trial. They just didn’t think it was important enough to mention that detail.

To the extent that one can trust the Stuff story at this point, there seem to be three reactions:

  • I don’t believe it because my opinions are more reliable than this research
  • Lunch would work even if breakfast didn’t
  •  We should be making sure kids have breakfast even if it doesn’t improve school performance.

The latter two responses are perfectly reasonable positions to take (though they’re more convincing where they were taken before the results came out).  School lunches might be more effective than breakfasts, and the US (hardly a hotbed of socialism) has had a huge school nutrition program for 60 years.

Still, if we’re going to supply subsidised meals to school kids, we do need to know why we’re doing it and what we expect to gain.    This study is one of the first to go beyond just saying that the benefits are obvious.

 

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Thomas Lumley (@tslumley) is Professor of Biostatistics at the University of Auckland. His research interests include semiparametric models, survey sampling, statistical computing, foundations of statistics, and whatever methodological problems his medical collaborators come up with. He also blogs at Biased and Inefficient See all posts by Thomas Lumley »

Comments

  • avatar
    Stuart McKay

    I thought the title “shotdown” was a little misleading. Without even reading the actual research one big flaw to me seemed to be:

    “Ni Murchu said there was a chance her study did not capture the children who most needed the breakfasts.

    “There’s always a risk that the kinds of people who participate are not the higher needs group.” This was because her study participants had to get parental consent and fill in a lengthy questionnaire – a process that may have alienated the high-needs families.”

    The principal also made a good point around that there is an education element around providing kids with nutritional breakfasts. I.e. it would normalising having healthy food instead of cocoa pops in our children.

    This is one study – Much more would be needed to sway me on something that seems intuitive.

    11 years ago

  • avatar
    Rachel Cunliffe

    Thanks for hunting down that it *was* a randomised trial; seemed unusual that a University research study hadn’t followed standard protocol.

    I wonder if there are other studies in progress in New Zealand right now investigating benefits of state-funded food programs?

    11 years ago

  • avatar
    Peter Green

    … this sample size will provide at least 85% power, with a significance level of α = 0.05, to detect a 10% absolute increase in the proportion of students with a school attendance rate of 95% or higher.

    A study this size is only going to find quite large effects. It’s not really surprising that it wasn’t powerful enough to measure any academic improvement.

    The study has a webpage. There’s a link to a presentation about the results, with a very interesting graph titled “Breakfast Everyday[sic]”. Providing breakfast didn’t appear to affect the number of students having breakfast, instead they were replacing home breakfasts with a more filling school breakfast. So the study raises interesting questions about delivery, but says very little about whether or not feeding hungry schoolkids will help them academically.

    11 years ago

    • avatar
      Thomas Lumley

      Power is irrelevant now: the study has been done, and we have confidence intervals.

      The 95% upper confidence limit for the impact on reading skills is 0.19 grades, so despite the study being relatively small, it rules out any really big effect of providing free breakfast.

      You say Providing breakfast didn’t appear to affect the number of students having breakfast, instead they were replacing home breakfasts with a more filling school breakfast. So the study raises interesting questions about delivery, but says very little about whether or not feeding hungry schoolkids will help them academically.

      The study doesn’t claim that hunger is irrelevant to education; it was a test of a specific intervention, which is quite close to the interventions actually being proposed for NZ schools, (and did have a fairly clear effect on reported hunger).

      The piece in Stuff made much stronger claims about shooting down the link between achievement and hunger, but the study didn’t.

      11 years ago