Unpublished studies hold twice as much data on drugs as those in public domain, study finds

Unpublished records of clinical studies provide more than twice as much information about a drug’s benefits and harms as those of published reports, a study has found.

The researchers, from Germany’s Institute for Quality and Efficiency in Health Care (IQWiG), said that access to clinical study reports (CSRs) was essential for doctors to be able to make fully informed choices about how to treat their patients. They have called for CSRs from past and future trials to be made publicly available.

CSRs hold vast amounts of information on the conduct, adverse events, and outcomes of a trial. They are held by drug companies and form the basis of submissions to drug regulators when a new drug is being assessed for …