Jan 17, 2014
Negative results: it's worth it!
other trials are not published at all, or trial outcomes are published selectively. One method of reducing, or at least detecting, publication bias is to require a description of all trials to be posted on a public register before the trials begin.
A recent study realized by Elizabeth Wager reveals what proportion of journals require trial registration as a condition for publication, or encourage it without making it mandatory, and why they choose to do this. This study was carried out by a quantitative analysis of journal requirements for trial registration from a sample of medical journals’ websites and a qualitative study of journal editors’ and publishers’ views on trial registration and publication bias.
A search of the CENTRAL database produced a list of 3512 journals. From a random sample of 200 journals, 142 (71%) did not require registration (or at least did not mention this on their website), 55 (28%) required registration, and 3 (2%) encouraged registration but did not make it a requirement for publication.
Some of the reasons for not requiring registration were fear of losing out to rival journals that do not require registration, doubts about the effectiveness of registration or fear of discouraging research from developing countries, which have different or no registration systems in place among others.
There were a lot of comments focused on the failure to publish studies with negative findings. However, during interviews it became apparent that the term “negative findings” or “negative trial” can be used to mean either those with statistically non-significant findings or those that, whether statistically significant or not, are viewed as unfavorable to a particular position (for example, a sponsor’s product or a hypothesis).
Interviewees were asked for their perceptions of the roles of different players such as authors, editors, and readers in publication bias. Key points that emerged were that authors do not submit reports of studies that produce statistically non-significant or unfavorable findings. One interviewee remarked “If you are a scientist and you obtain a negative [rather than a positive] result, your first reaction is to try and make it work differently, and if it doesn’t work, you don’t pursue that line of research.” That’s a big problem.
Although highlighting author practices that lead to publication bias, the editors interviewed did generally assume considerable responsibility because some of them simply “don’t publish negative trials”. A curious reason given by one interviewee was “If somebody submits a paper from Iran, for example, the barrier is higher for them and it’s biased in both the fact that they have to be able to generate a paper that is written in coherent English and also biased because the focus of our journal is for . . . members of the [an American learned society] . . . so you would . . . reject out of hand papers that talk about . . . the Persian population.”
Regarding readers, it is suggested that they play a role in causing or perpetuating publication bias through their preference for positive findings.
There was a minority view that commercial funders, in particular pharmaceutical companies, might suppress negative findings because of the dissemination of all findings should be an obligation on the part of the funding bodies.
Possible solutions: Several interviewees mentioned journals specifically designed to publish negative results, something facilitated by the potential of open access journals.
This study suggests that journal editors may not believe that the benefits of trial registration are sufficiently important to be a mandatory requirement, or have concerns that requiring registration as a condition of publication would harm their journal, or both. As one editor (referring to small trials), said “it hardly seems worth the effort.”
Still, I think that yes, it's worth it.
Adapted by Dr. Belén Suárez for The All Results Journals.