Comparison of serious adverse events posted at ClinicalTrials.gov and published in corresponding journal articles.
BACKGROUND
The reporting of serious adverse events (SAEs) in clinical trials is crucial to assess the balance between benefits and risks. For trials with serious adverse events posted at ClinicalTrials.gov, we assessed the consistency between SAEs posted at ClinicalTrials.gov and those published in corresponding journal articles.


METHODS
All records from ClinicalTrials.gov up to February 2014 were automatically exported in XML format. Among these, we identified all phase III or IV randomized controlled trials with at least one SAE posted. For a random sample of 300 of these trials, we searched for corresponding publications using MEDLINE via PubMed and extracted safety results from the articles.


RESULTS
Among the sample of 300 trials with SAEs posted at ClinicalTrials.gov, 78 (26%) did not have a corresponding publication, and 20 (7%) had a publication that did not match the ClinicalTrials.gov record. For the 202 remaining trials, 26 published articles (13%) did not mention SAEs, 4 (2%) reported no SAEs, and 33 (16%) did not report the total number of SAEs per treatment group. Among the remaining 139 trials, for 44 (32%), the number of SAEs per group published did not match those posted at ClinicalTrials.gov. For 31 trials, the number of SAEs was greater at ClinicalTrials.gov than in the published article, with a difference ≥30 % for at least one group for 21. Only 33 trials (11%) had a publication reporting matching numbers of SAE and describing the type of SAE.


CONCLUSIONS
Many trials with SAEs posted at ClinicalTrials.gov are not yet published, omit the reporting of these SAEs in corresponding publications, or report a discrepant number of SAEs as compared with ClinicalTrials.gov. These results underline the need to consult ClinicalTrials.gov for more information on serious harms.
Columbia University, Mailman School of Public Health, New York, NY, USA. eveystang@gmail.com.
Eve
E
Tang
Columbia University, Mailman School of Public Health, New York, NY, USA. philipperavaud@gmail.com.|Centre de Recherche Epidémiologie et Statistique, Inserm U1153, Hôpital Hôtel-Dieu, 1 place du Parvis Notre Dame, 75004, Paris, France. philipperavaud@gmail.com.|Université Paris Descartes - Sorbonne Paris Cité, Paris, France. philipperavaud@gmail.com.|Assistance Publique-Hôpitaux de Paris, Hôpital Hôtel-Dieu, Centre d'Epidémiologie Clinique, Paris, France. philipperavaud@gmail.com.|Cochrane France, Paris, France. philipperavaud@gmail.com.
Philippe
P
Ravaud
Centre de Recherche Epidémiologie et Statistique, Inserm U1153, Hôpital Hôtel-Dieu, 1 place du Parvis Notre Dame, 75004, Paris, France. carolina.riveros@aphp.fr.|Assistance Publique-Hôpitaux de Paris, Hôpital Hôtel-Dieu, Centre d'Epidémiologie Clinique, Paris, France. carolina.riveros@aphp.fr.
Carolina
C
Riveros
Centre de Recherche Epidémiologie et Statistique, Inserm U1153, Hôpital Hôtel-Dieu, 1 place du Parvis Notre Dame, 75004, Paris, France. elodie.perrodeau@gmail.com.|Assistance Publique-Hôpitaux de Paris, Hôpital Hôtel-Dieu, Centre d'Epidémiologie Clinique, Paris, France. elodie.perrodeau@gmail.com.
Elodie
E
Perrodeau
Centre de Recherche Epidémiologie et Statistique, Inserm U1153, Hôpital Hôtel-Dieu, 1 place du Parvis Notre Dame, 75004, Paris, France. agnes.dechartres@aphp.fr.|Université Paris Descartes - Sorbonne Paris Cité, Paris, France. agnes.dechartres@aphp.fr.|Assistance Publique-Hôpitaux de Paris, Hôpital Hôtel-Dieu, Centre d'Epidémiologie Clinique, Paris, France. agnes.dechartres@aphp.fr.|Cochrane France, Paris, France. agnes.dechartres@aphp.fr.
Agnes
A
Dechartres
D022126:Access to Information; D016907:Adverse Drug Reaction Reporting Systems / Q000706:statistics & numerical data*; D002986:Clinical Trials as Topic / Q000379:methods / Q000706:statistics & numerical data; D064420:Drug-Related Side Effects and Adverse Reactions; D006801:Humans; D011642:Publications / Q000592:standards / Q000706:statistics & numerical data; D011643:Publishing / Q000592:standards / Q000706:statistics & numerical data; D012107:Research Design / Q000592:standards*; D012720:Severity of Illness Index