Hello and welcome to more or less on the BBC World Service. We are weekly guide to the numbers all around us in the news and in life. And I'm Tim Halford.

Are you, like me, a parent, anxiously and somewhat helplessly watching your 16 year old offspring enduring a summer of exams?

Don't you wish you could do more to help them out? Well, if you believe the newspapers, there is an easy solution.

Simply travel back in time, 16 years and breastfeed your baby for as long as you possibly can.

Breastfeeding for longer may be linked to better exam results.

Kids breastfed for at least a year, a 38% more likely to get A's in exams, study finds.

That is a big number, but what on earth should we make of it?

These headlines were linked to a study by researchers at Oxford University. They looked at the link between being breastfed as a baby and pass rates in the GCSE exams in English and maths, which are given to many 16 year old students in England, Northern Ireland and Wales.

The study concluded that a longer breastfeeding duration was associated with what it called modest improvements in educational outcomes at age 16.

But 38% doesn't sound like a modest improvement to me, and what do they mean by associated anyway?

Such questions also occurred to some of our loyal listeners who emailed more or less at BBC.co.uk to say...

I would love to hear your thoughts on the latest study claiming that breastfed babies have better exam results.

The study claims that socioeconomic factors have been taken into account, but makes no mention of preschool education, opportunities for extracurricular activities or indeed fathers.

I don't want to get into a breast versus bottled debate, but do we have a correlation is not causation situation going on here?

On my way to work last week, while listening to the BBC Radio 4 News, I was surprised to find out that I would be to blame for my children potentially lower GCSE results.

They will not fulfill their true potential because I did not breastfed them for a full year.

Is there a causal relationship between breastfeeding and exam attainment?

And your usual good analysis would be very helpful here.

Your wish is our command.

So what does this study really tell us about whether you can breastfeed your baby into educational success?

Emily Oster is a professor of economics at Brown University in the United States and the author of three books about pregnancy and parenting.

What this paper does is it relates a measure of test scores at the age of 16 to breastfeeding behavior when kids were obviously very young.

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