Source: British Medical Journal (UK) Contact: Sat, 23 May 1998 Author: Jacqui Wise, BMJ LINKS TO TOBACCO INDUSTRY INFLUENCES REVIEW CONCLUSIONS A review article written by authors with affiliations to the tobacco industry is 88 times more likely to conclude that passive smoking is not harmful than if the review article was written by authors with no connection to the tobacco industry. Deborah Barnes and Lisa Bero from the University of California searched Medline and Embase and a database of symposium proceedings on passive smoking and identified 106 reviews of the health effects of passive smoking published from 1980 to 1995 (JAMA 1998; 279:1566-70). They found that very few reviews had been conducted systematically. Three quarters of the articles failed to disclose the sources of funding for the research. Overall 39 of the reviews concluded that passive smoking is not harmful to health--and 31 of these were written by authors who had affiliations with the tobacco industry. There was a strong relation between the conclusion of a review and the affiliation of its authors--29 (94%) of the reviews by authors with links to the tobacco industry concluded that passive smoking is not harmful, compared with 10 (13%) of the 75 reviews by authors without such affiliations. The authors wrote: "No matter how we analysed the data, tobacco industry affiliation was the only factor associated with concluding that passive smoking is not harmful to health in the multivariate analyses." Ms Barnes and Dr Bero wrote: "These findings suggest that the tobacco industry may be attempting to influence scientific opinion by flooding the scientific literature with large numbers of review articles supporting its position that passive smoking is not harmful to health". - --- Checked-by: (Joel W. Johnson)