Michael Williams: So when is a news story not a news story? Discuss

I once worked for an editor who frequently lectured his journalists: "You don't have to reinvent the wheel every week." He was referring to the tendency of all reporters to think only of the "new" and to discard anything published before, no matter how brief the reference or obscure the place of publication. Of course, being "first with the latest" is the traditional way to sell newspapers, and "newshounds" are just that – trained to sniff out the newest news. But "newness" can become an obsession in itself.

I thought about this after a grumpy email last week from reader Mary Donaldson in Girvan, Ayrshire, who writes: "The report on your front page last week 'revealing' the link between smoking and cot death was hardly a revelation to me. I am a nurse working in a GP practice and it has long been standard advice to mothers in Scotland that they should not smoke while pregnant or near their babies. To my knowledge, lots of studies have already shown a link between smoking and sudden infant death. What's new?"

So I checked the "cuttings" (as the publication records are still quaintly called in this digital age). Certainly, there has been lots of evidence in the past to link cot deaths with smoking – some researchers suggesting it can increase the risks by up to fivefold. A major study in Queensland, Australia, said so in 2002, as did another at the University of Arizona in 2003.

So last Sunday's story was not the first time the link had been established. But it was a genuine "revelation" in that the 'IoS' had got hold of yet more unpublished evidence to drive home the point. The Bristol University Institute of Child Health study showed that nine out of 10 mothers whose babies suffered cot death had smoked during pregnancy.

With all medical research, it is not usually a single "whizz-bang" fact that makes the difference, but rather the accumulation of a body of evidence over time. Cigarettes were linked to lung cancer long before the famous and hugely influential report from the Royal College of Physicians 45 years ago. But the quality and weight of that research forced the government to take decisive action against smoking and so changed the habits of the population.

There are still dissenters over the degree to which tobacco consumption is responsible for cot death – several have their say in the 'IoS' blogs this week (www.ios.typepad.com). But the publication of the Bristol University research – given, I believe, rightful front-page prominence – could be the tipping point that gets ministers to take action to protect our most vulnerable children.

Corrections and clarifications

Spelt flour, whose origins go back to Roman times, is one of the latest cult health foods. But it is not gluten-free, as we have stated twice recently. It contains wheat and is not safe for people who need a gluten-free diet. Spelt flour can be toxic to people with coeliac disease. There was also an error on our article about Samantha Cameron last week. We have been asked to point out that Stuart Vevers, the design director of Mulberry, has not yet left the company and that his successor, Katie Grand, does not join until the beginning of next year.

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