Article type
Year
Abstract
Background: To control for selective reporting, registering each study at inception in a public register is advocated. After registration an unique registration number is assigned to each study which enables identification of future publications and increases transparency. The International Committee of Medical Journal Editors (ICMJE) therefore recommends reporting of the registration number at the end of the abstract.
Objective: To asses the reporting of unique trial identification numbers in biomedical publications.
Methods: We searched the Netherlands Trial Register (NTR) for all randomized clinical trials (RCTs) registered in 2005 that notified study completion by August 31, 2008. We used the unique identification number to search MEDLINE for publications. If no publication was found, the author’s name(s) or elements of the title were used to identify possible publications or we contacted the primary author. We also evaluated whether the journals in which the studies were published were following the ICMJE’s Uniform Requirements for Manuscripts (URM).
Results: We included 542 RCTs. Of those, 282 (52%) were published, of which 164 (58%) had reported the trial identification number (yet not necessarily at the end of the abstract). Of the remaining 118 trials, 55 (47%) were published in ICMJE journals.
Conclusions: A substantial percentage of registered trials did not report the trial registration number in the abstract of their publication. Almost half of those were published in ICMJE journals that ideally should follow their own recommendations. Hence, there seems to be a need to promote accurate reporting of trial identification numbers to enable easy identification of published reports of registered studies. This could possibly be done by adding the unique trial identification number as an item to the CONSORT checklist.
Objective: To asses the reporting of unique trial identification numbers in biomedical publications.
Methods: We searched the Netherlands Trial Register (NTR) for all randomized clinical trials (RCTs) registered in 2005 that notified study completion by August 31, 2008. We used the unique identification number to search MEDLINE for publications. If no publication was found, the author’s name(s) or elements of the title were used to identify possible publications or we contacted the primary author. We also evaluated whether the journals in which the studies were published were following the ICMJE’s Uniform Requirements for Manuscripts (URM).
Results: We included 542 RCTs. Of those, 282 (52%) were published, of which 164 (58%) had reported the trial identification number (yet not necessarily at the end of the abstract). Of the remaining 118 trials, 55 (47%) were published in ICMJE journals.
Conclusions: A substantial percentage of registered trials did not report the trial registration number in the abstract of their publication. Almost half of those were published in ICMJE journals that ideally should follow their own recommendations. Hence, there seems to be a need to promote accurate reporting of trial identification numbers to enable easy identification of published reports of registered studies. This could possibly be done by adding the unique trial identification number as an item to the CONSORT checklist.