The research, to be published later this year, covers 22 countries in the Organisation for Economic Co-operation and Development, including six which have brought in a ban. It was commissioned by the European tobacco industry and described yesterday by the Advertising Association, which is lobbying strongly against a ban, as 'the most comprehensive analysis ever produced'.
Its author, Michael Stewart, an independent statistical consultant, insisted his study was free of bias. 'I was told to analyse the data impartially. It is possible the analysis would not have seen the light of day if it had shown there was a link between advertising and consumption. But I think it is a fairly meticulous piece of work.'
Mr Stewart said his study, which shows a small but 'not quite statistically significant' increase in smoking where advertising has been banned, 'clearly refutes' the link with advertising. His explanation is that 10 to 15 per cent of advertising space is taken up with health warnings.
The 'equivalent of millions of ecus of ongoing anti-smoking advertising across the European Community' would thus disappear with a ban, he argues.
The Health Education Authority said yesterday it believed a ban on advertising was 'integral' to reducing smoking. 'The industry can work research the way it wants to,' a spokesman said.
Both sides in the debate have been lobbying the Department of Health since the publication last October of a report by Clive Smee, its chief economic adviser, which suggested that a ban could reduce smoking by more than 7 per cent.
The deadline for responses to the Smee report expired yesterday. This month, the Commons health committee came out in favour of a ban, but Virginia Bottomley, Secretary of State for Health, said the Government remained opposed to it.
Both the Advertising Association and Mr Stewart yesterday criticised the Smee report and the New Zealand study on which it was largely based for poor methodology. Mr Stewart said the Smee report contained 'schoolboy howlers' and was not originally intended for publication.
The Stewart findings have been adjusted to take account of factors such as price, age profiles and cultural differences - they may thus conflict with straightforward figures for tobacco consumption. They suggest that smoking in countries with a ban has increased in relation to non-ban countries in four out of six cases.
In Iceland, which has had a ban since 1971, the study says consumption has been on average 9 per cent higher. Other examples are Norway (ban since 1975), no change; Finland (1978), up 11 per cent; Italy and Portugal (1983), up 4 per cent. Only Canada, which banned advertising in 1988, saw a reduction, of 5 per cent.
Mike Waterson, the association's research adviser, said unadjusted tobacco consumption in Norway since 1975 had fallen by 0.5 per cent, but in the UK, where there has been no ban, it was down by 28 per cent. The industry argues that advertising is necessary to maintain brand share in a 'virulently competitive' market.
Mr Waterson acknowledged that 'absolute, conclusive proof' was unlikely. 'It is impossible to say that advertising has not caused one child to smoke. But I believe the balance of evidence is massively on our side.'Reuse content