A dozen of the top medical journals announced in August a policy of rejecting drug company-sponsored studies that do not guarantee scientific independence to researchers or supply them with all the data.

Publications that have agreed to publish a joint statement in mid-September outlining the new policy include the New England Journal of Medicine, Lancet, the Journal of the American Medical Association, the Canadian Medical Association Journal, the Annals of Internal Medicine and the British Medical Journal.

The journal editors say they will make the researchers accountable for the studies they submit for publication by signing a form acknowledging authorship and "responsibility for all the data."

It is hoped the new policy will give researchers more leverage in dealing with the pharmaceutical industry which is eager to have studies published in these journals because doctors view them as credible sources of information in helping decide what to prescribe.

Marcia Angell, former editor-in-chief of the New England Journal of Medicine said in large, company-sponsored drug trials involving multiple hospitals all of the information is typically held by the company and not even the principal investigator may see all of the data.

The international science journal Nature is going one step further. On Aug. 23 it announced it would start asking authors to disclose financial conflicts of interest in their submitted papers. The journal will release the information with the published papers.

Nature editor Philip Campbell said the policy is meant to "maintain readers' trust in the integrity of the research we publish. If financial interests are disclosed, readers will be able form their own judgements of possible bias."