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: jwjohnson@netmagic.net (Joel W. Johnson)