In an article neatly titled the write position, Jonathan D. Wren et al. in the current issue of EMBO Reports ( 8, 11, 998-991; 2007 ) survey perceived contributions to papers in biomedical fields based on byline position and number of authors. They undertook the study because publications in peer-reviewed journals are a major criterion for assessing scientists for promotion, tenure or funding, yet not all authors are viewed as equal contributors. Qualitatively, those listed first or last in the byline are generally apportioned more credit for the work than middle authors, but it is not known exactly how much authors are perceived to contribute from their byline position.

To attempt a quantitative assessment, the authors surveyed chairpeople of promotion and tenure committees, and found that respondents felt that the first author in a three-person byline had made the greatest contribution to the work performed, whereas the last author deserved most credit for both the initial conception and supervision of the project. There was no significant difference in three-author compared with five-author bylines for the credit apportioned to the last author for initial conception, work performed or supervision.

In addition, nearly half of the repondents agreed that granting authorship to someone who does not meet journal authorship criteria is common. Adding authors to a publication apparently does not affect the relative overall credit afforded to the last author, but the perceived contributions of all other authors suffer a drop in value.

For details of survey response rates and percentages, as well as further information, please see the full report at the EMBO Reports website.