WEDNESDAY, Oct. 26 (HealthDay News) -- Honorary and ghost authors were involved in 21 percent of articles published in six leading medical journals in 2008, which shows that this type of inappropriate authorship remains a problem, a new study says.

Honorary authors are people named as authors despite not making a substantial enough contribution to take responsibility for the research. Ghost authors are people who play a major role in the research or who participate in writing the article, but are not named as authors.

The lack of transparency and accountability associated with both types of inappropriate authorship has been a concern for decades, according to the study authors.

More than 600 biomedical journals have adopted guidelines for responsible and accountable authorship established by the International Committee of Medical Journal Editors, but previous research has found that the prevalence of honorary authors in articles is as high as 39 percent and the use of ghost authors as high as 11 percent.

In this new study, U.S. researchers compared the prevalence of honorary and ghost authors in articles published in six leading medical journals in 1996 and 2008.

Information from 630 authors who responded to the researchers' survey showed that the overall prevalence of articles with inappropriate authorship fell from 29 percent in 1996 to 21 percent in 2008.

There was no change in the prevalence of honorary authors over that time, but there was a large decline in the prevalence of ghost authors.

Original research articles had higher rates of both types of inappropriate authorship than review articles or editorials.

The study was published online Oct. 25 in the British Medical Journal.

"Increased efforts by scientific journals, individual authors and academic institutions are essential to promote responsibility, accountability and transparency in authorship, and to maintain integrity in scientific publication," the researchers wrote in a journal news release.

More information

The International Committee of Medical Journal Editors outlines its standards for authorship and contributorship.