Brian Monteith: See through this smokescreen on children's health

There is no doubt that at this time in our history the esteem of politicians is at a pretty low ebb. Journalists have never been especially well regarded, so, as an ex-politician who has turned to writing, my personal stock is more a sell, sell, sell than a buy, buy, buy.

Then there's the undeniable fact that I am of a Conservative disposition, which in Scotland puts my popularity on a par with Ratner's jewellery, and just as fashionable. To add to this, my background is nearly 30 years as a public relations consultant. Once a spin-doctor, then a Tory politician-cum-journalist - I suppose it could have been worse, I might have been a lawyer.

Of course, there are good politicians and bad, good lawyers and bad, so it is actually lazy to generalise; but why is it that we seem so accepting, so gullible even, of what scientists tell us? Do scientists not have their own agendas, their own personal motivations that might get in the road of their objectivity when it comes to telling us what they have been researching?

I pondered this when, last week, I read a report of a study published by Professor Jill Pell that claimed the smoking ban in public places had led to a fall in hospital admissions of children with asthma by more than 18 per cent.

Even for opponents of the smoking ban in public places, such as myself, this seemed an impressive claim that strengthened the case for what I believe was a disproportionate response to the highly marginal, if not unproven, risk of second-hand tobacco smoke.

I looked at the figures buried in the report. Lo and behold, I found what appears to be another example of that modern trait that in television is called dumbing-down, in politics is called reaching for the lowest common denominator and in research is called junk science.

The claim of Prof Pell is quite simple: "Before the smoking ban came into force, admissions for asthma were increasing at a mean rate of 5.2 per cent a year. After the ban, admissions decreased by 18.2 per cent per year, relative to the rate on 26 March, 2006."

My first reaction was to think that, although most people might think that reducing the possibility of children inhaling the tobacco smoke of others would be a good thing in general and a great thing for children, the smoking ban could surely only have a marginal effect. Smoking was already banned in practically all public buildings, certainly all classrooms, sports venues, playcentres, or even in McDonald's and other places children might congregate.The main effect of the smoking ban - to outlaw smoking in the workplace - should not matter to children, even most restaurants had no-smoking areas or no smoking at all, and children were generally not allowed in Scottish pubs. In fact, it would be reasonable to expect that more adults are smoking at home in the vicinity of the children than before. So why would there be fewer hospital admissions?

Then it became apparent; looking at the figures, Prof Pell's headline claim was unjustifiable. The highest number of admissions in the past ten years was 2,633 in 2006 - the year when the smoking ban came into effect. In fact, for all of the years between 2000 to 2005, the number of admissions was lower, in 2003 falling to 1,803.

What the figures reveal is that after the smoking ban there is at best a see-saw of admissions - but no perceptible trend.

Using the government's own health statistics reveals no obvious trend to back up Pell's claim. Using the financial year as opposed to the calendar year, which is more helpful as the smoking ban came into effect at the end of March 2006, the NHS figures show the same peak in the year after the smoking ban, with the years before and after both being lower.

By choosing to look at the asthmatic admissions for children for the ten-month period of 2009 against the peak year of 2006, when the ban was introduced, Pell can demonstrate the most extravagant variation - but not one that matches against the other years before the smoking ban. In other words, a sleight of hand that would put spin-meisters, such as Alastair Campbell, to shame has been perpetrated on the unsuspecting public.

This should not come as a surprise, it was the same Jill Pell that in 2007 told the world, at a conference held in Edinburgh, to extol the effects of the Scottish smoking ban that admissions for heart attacks had fallen by 17 per cent.

She claimed that, "What we were able to show is that among people who are non-smokers there was a 20 per cent reduction in heart attack admissions. This confirms that the legislation has been effective in helping non-smokers."

Prof Pell's study was a masterclass in how comparing one set of statistics with another group that sounded similar but were quite different can be accepted into political folklore. It is like comparing lemons with limes: they might both be citrus fruits, but they have quite different tastes and appearances.

Greater inspection of the statistics revealed that using NHS estimates the reduction was about 8 per cent - similar to the previous trends already being obtained before the smoking ban. Indeed, in the second year of the smoking ban, the number of ARC admissions rose (from 16,199 in 2005-6 to 16,212 in 2006-7).

The cause of asthmatic attacks remains a controversial area, with studies in Sweden claiming such factors as fitted carpets in bedrooms as the problem, while studies elsewhere suggest hard floors offer greater risk.A study of 4,600 New Jersey children found that, for pre-school children, damp bathrooms and mould were the only household factors associated with asthma diagnosis.

The claim made about hospital admissions of children with asthma attacks being reduced due to less exposure to tobacco smoke is, at best, spurious.

If research scientists are not to win the scurrilous reputation enjoyed by politicians they should be careful of what they claim in the public domain.