A new study published in the open source journal PLoS Medicine demonstrates that most of the clinical drug studies the researchers examined had one or more “ghost authors.” Ghost authorship is the failure to attribute authorship of a study to an individual who has made a substantial contribution to the study. A examination of 44 industry-initiated trials from Denmark in the 1990s found evidence of ghost authorship for 33 trials, which increased to 40 trials if a person qualifying for authorship was just acknowledged rather than being named as an author.

The researchers, led by Peter C. Gøtzsche from the Nordic Cochrane Centre, Copenhagen, Denmark, studied all published industry-initiated randomised trials approved in 1994–1995 by the Scientific-Ethical Committees for Copenhagen and Frederiksberg in Denmark. They compared the full trial protocols (which were written before the trial was begun) approved by these ethical committees with the primary scientific report which resulted from these trials, and which was published in a peer-reviewed journal.

Ghost authorship was defined as present if individuals who wrote the trial protocol, performed the statistical analyses, or wrote the manuscript, were not listed as authors of the publication, or as members of a study group or writing committee, or in an acknowledgment. Of the 44 trials included, 43 were initiated by one of 26 multinational pharmaceutical firms and one by a local company.

In 31 trials, the ghost authors identified were statisticians. Eight publications acknowledged the assistance of statisticians, and four acknowledged the assistance of medical writers. Conversely, although all published reports had clinicians as authors no trial protocol or publication stated explicitly that the study report or the manuscript was to be written or was written by the clinical investigators, and none of the protocols stated that clinical investigators were to be involved with data analysis. It was also unclear whether clinicians had contributed to the protocols.

This study is the first that has systematically examined the prevalence of ghost authorship using a cohort of protocols and corresponding publications. The authors conclude that “ghost authorship in industry-initiated randomised trials is very common, and we believe that this practice serves commercial purposes”. They go on to urge that in order to reduce the prevalence of ghost authorship existing guidelines, such as those drawn up by the International Committee on Medical Journal Editors, World Association of Medical Editors and European Medical Writers Association are followed. This action could increase the chance that publications accurately, fairly, and comprehensively reflect the data collected from trials

Read the full study on PLoS Medicine.