A leading medical journal is launching a global campaign to separate medicine from big pharma, linking industry influence to the pelvic mesh scandal that injured hundreds of women.

The BMJ says doctors are being unduly influenced by industry-sponsored education events and industry-funded trials for major drugs.

Those trials cannot be trusted, the journal's editor and a team of global healthcare leaders write in a scathing editorial published on Wednesday.

The "endemic financial entanglement with industry is distorting the production and use of healthcare evidence, causing harm to individuals and waste for health systems", they write.

They are calling for governments to start funding independent trials of new drugs and medical devices, rather than relying on industry-funded studies. Sponsored research is more likely to find a favourable result compared to independent research, studies show.