Source: Scotsman (UK) Contact: http://www.scotsman.com/ Pubdate: Sat, 1 Aug 1998 Author: JENNIFER TRUELAND, Heath Correspondent PASSIVE SMOKING RESEARCH CALLED INTO QUESTION DOUBT has been cast on scientific research which, it claimed, overestimated the dangers of passive smoking. The studies, published in the 'British Medical Journal' last October, claimed that people who had never smoked had a 25 per cent greater chance of developing lung cancer and heart disease if they lived with a smoker. But scientists, researchers, doctors and statisticians have taken issue with the findings, claiming that the authors had disregarded result which did not agree with their interpretation of available data. In letters published in today's 'BMJ', one researcher says there are better ways to spend money than vilifing passive smoking, while another says the evidence needs re-evaluation. The original studies sparked a reaction from Tessa Jowell, the public health minister, whe said they reinforced the compelllng case for reducing smoking. The British Medical Association's science and research adviser said the evidence showed living with a smoker was a major health hazard. But in today's 'BMJ', Peter Lee, an independent consultant in statistics and epidemiology, is critical of the previous studies. He says that the authors should have included other research which would have distorted their findings and that they based part of their conclusions on unreliable evidence. He adds: "One might even argue that the authors have not conclusively demonstrated that passive smoking has any effect on risk of lung cancer." In another letter to the 'BMJ', Dr Kenneth Denson, the director of Thames Thrombosis and Haemostasis Research Foundation in Oxfordshire, says the studies did not allow for other variables, such as diet. In any case, he says: "We know the score on active smoking, but surely the money spent on these attempts at vilifying passive smoking could be better spent in other areas of the NHS." The BMJ's editor, Dr Richard Smith, warns that medical studies coud be flawed by conflicts of interest. Of 106 review articles on passive smoking, 37 per cent had concluded it was not harmful - three quarters of these written by researchers with connections to tobacco companies. Dr Smith says authors may not realise that they had been influenced. "Our response is that bias works in subtle ways and that none of us is blessed with knowledge of our own motivations and mental mechanisms." he said. - ---