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Misleading abstract

Posted by AdamJacobs on 25 Jul 2013 at 13:00 GMT

The abstract of this article states:

"Our results show that most trials do not report results"

This is highly misleading. What the results show is that most trials do not link to results in a structured manner. As was acknowledged in the full paper, it is possible that many trials did not link to results in a structured manner, and yet the results still exist and could be found by a manual literature search.

This study has not shown what proportion of trials do or do not report results.

Competing interests declared: I run a company that provides publication services to pharmaceutical companies, medical device companies, and academic researchers.

RE: Misleading abstract

vojtech_huser replied to AdamJacobs on 02 Aug 2013 at 15:02 GMT

Author reply:

We acknowledge that the sentence, when taken out of the abstract context, may be viewed as misleading; however, in the second sentence of the abstract, we clearly define that we only considered linked articles in our analysis.

We also discuss this issue (as pointed by the commented) in the full article.
Furthermore, we tried to estimate how often an unlinked result article exists. In our earlier work (Ref 13; Huser V, Cimino JJ (2012) Precision and Negative Predictive Value of Links between ClinicalTrials.gov and PubMed. AMIA Annu Symp Proc, 2012: 400-408. PubMed: 23304310; available at: https://www.researchgate....) we measured how often an unlinked result article exists. This is also mentioned in the ‘Limitations section’). The article says:’ A prior study of negative predictive value of trial-article links [13] shows that 44% of trials with no linked result articles indeed have an unlinked result article that can be found by manually searching PubMed.’

In addition, it is possible to calculate a corrected estimate: If we extrapolate the unlinked article rate of 44% to our linked-only results - that for the trials without result article (2477/8907; 27.8%), indeed 44% have unlinked result article ((2477*0.44=1089 trials), we would get a corrected rate of having a linked or unlinked result article of 40% [(2477+1089)/8907] instead of reported linked-article only rate of 27.8%.

No competing interests declared.