Difficulty in detecting discrepancies in a clinical trial report: 260-reader evaluation

Abstract

Background: Scientific literature can contain errors. Discrepancies, defined as two or more statements or results that cannot both be true, may be a signal of problems with a trial report. In this study, we report how many discrepancies are detected by a large panel of readers examining a trial report containing a large number of discrepancies.Methods: We approached a convenience sample of 343 journal readers in seven countries, and invited them in person to participate in a study. They were asked to examine the tables and figures of one published article for discrepancies. 260 participants agreed, ranging from medical students to professors. The discrepancies they identified were tabulated and counted. There were 39 different discrepancies identified. We evaluated the probability of discrepancy identification, and whether more time spent or greater participant experience as academic authors improved the ability to detect discrepancies.Results: Overall, 95.3% of discrepancies were missed. Most participants (62%) were unable to find any discrepancies. Only 11.5% noticed more than 10% of the discrepancies. More discrepancies were noted by participants who spent more time on the task (Spearman’s ρ = 0.22, P < 0.01), and those with more experience of publishing papers (Spearman’s ρ = 0.13 with number of publications, P = 0.04).Conclusions: Noticing discrepancies is difficult. Most readers miss most discrepancies even when asked specifically to look for them. The probability of a discrepancy evading an individual sensitized reader is 95%, making it important that, when problems are identified after publication, readers are able to communicate with each other. When made aware of discrepancies, the majority of readers support editorial action to correct the scientific record.

Data extraction methods: an analysis of internal reporting discrepancies in single manuscripts and practical advice

“…Suggestions for systematic review authors on how to address internal reporting discrepancies editorial and peer-review process, as well as galley proof checking, should also be highlighted as measures for preventing objective errors. As Cole et al [15] have observed, ''Even minor discrepancies should not be neglected, as they may be the tip of an error iceberg''.…”

“…However, some discrepancies were major, potentially reverting results in a meta-analysis or causing complete misinterpretation of results. It has also been previously emphasized that discrepancies can be a sign of deeply problematic studies, warranting further attention and verification [15]. The judgment of the relevance of discrepancies should be always collegial, involving more reviewers.…”

“…Cole et al [15] have shown that it is difficult for readers of research manuscripts to notice discrepancies: in their study, they included 343 readers and found that 95.3% of discrepancies were missed. Reviewers of primary studies are, instead, a selected group of readers of primary articles: they carefully examine study data, extracting them in structured formats.…”

“…However, as Cole et al [15] have shown, discrepancies can also be found within a single manuscript published in a scientific journal. Even multiple peer reviews, copyediting, and revision of galley proof by original authors do not completely protect against the hazard of making one or more errors.…”

Declaring interests and restoring trust in medicine

“…Little agreement exists on what constitutes effective peer review or the skills required to provide it,6 and there is little evidence that peer review does what many think it should do—ensure the quality of research 7. Although peer review is highly regarded by researchers and considered essential for publication of research8 it has many flaws: In one study, 607 peer reviewers for The BMJ detected only one third of major errors inserted into test trial reports, despite training;9 In another, 260 readers missed 95% of the 39 discrepancies in a clinical trial report 10. Peer review itself is of questionable value and could offer false reassurance.…”