Daniel M. Hartung, PharmD, MPH; Deborah A. Zarin, MD; Jeanne-Marie Guise, MD, MPH; Marian McDonagh, PharmD; Robin Paynter, MLS; Mark Helfand, MD, MS, MPH
Disclaimer: The content of this article is solely the responsibility of the authors and does not necessarily represent the official views of the National Library of Medicine or the Agency for Healthcare Research and Quality.
Acknowledgment: The authors thank Luke Middleton, BS, for developing the abstraction tool and database and Kaylee Williamson, BS, PharmD candidate, for assisting in sample validation.
Financial Support: By contract HHSN 276-2009-00128P from the National Library of Medicine and grant K12HS019456 from the Agency for Healthcare Research and Quality. Dr. Hartung received support from an Agency for Healthcare Research and Quality career development award (K12 HS019456). Dr. Zarin was funded by the intramural research program of the National Library of Medicine.
Potential Conflicts of Interest: Disclosures can be viewed at www.acponline.org/authors/icmje/ConflictOfInterestForms.do?msNum=M13-0480.
Requests for Single Reprints: Daniel M. Hartung, PharmD, MPH, Oregon State University/Oregon Health & Science University, College of Pharmacy, 3303 SW Bond Avenue, CH12C, Portland, OR 97239; e-mail, email@example.com.
Current Author Addresses: Dr. Hartung: Oregon State University/Oregon Health & Science University, College of Pharmacy, 3303 SW Bond Avenue, CH12C, Portland, OR 97239.
Dr. Zarin: National Library of Medicine, 8600 Rockville Pike, Bethesda, MD 20894.
Dr. Guise: Oregon Health & Science University, Department of Obstetrics and Gynecology, 3181 SW Sam Jackson Park Road, Portland, OR 97239.
Dr. McDonagh and Ms. Paynter: Oregon Health & Science University, Department of Medical Informatics and Clinical Epidemiology, Mail Stop BICC, 3181 SW Sam Jackson Park Road, Portland, OR 97239.
Dr. Helfand: Portland VA Medical Center, Hospital and Specialty Care Division, Mail Code P3MED, Portland, OR 97239.
Author Contributions: Conception and design: D.M. Hartung, D.A. Zarin, M. McDonagh, M. Helfand.
Analysis and interpretation of the data: D.M. Hartung, D.A. Zarin, J.M. Guise, M. McDonagh, R. Paynter, M. Helfand.
Drafting of the article: D.M. Hartung, J.M. Guise, M. McDonagh, M. Helfand.
Critical revision of the article for important intellectual content: D.M. Hartung, D.A. Zarin, J.M. Guise, M. McDonagh, M. Helfand.
Final approval of the article: D.M. Hartung, D.A. Zarin, J.M. Guise, M. Helfand.
Provision of study materials or patients: D.M. Hartung.
Statistical expertise: D.M. Hartung, M. Helfand.
Obtaining of funding: M. Helfand.
Administrative, technical, or logistic support: D.A. Zarin, J.M. Guise, M. Helfand.
Collection and assembly of data: D.M. Hartung, R. Paynter.
ClinicalTrials.gov requires reporting of result summaries for many drug and device trials.
To evaluate the consistency of reporting of trials that are registered in the ClinicalTrials.gov results database and published in the literature.
ClinicalTrials.gov results database and matched publications identified through ClinicalTrials.gov and a manual search of 2 electronic databases.
10% random sample of phase 3 or 4 trials with results in the ClinicalTrials.gov results database, completed before 1 January 2009, with 2 or more groups.
One reviewer extracted data about trial design and results from the results database and matching publications. A subsample was independently verified.
Of 110 trials with results, most were industry-sponsored, parallel-design drug studies. The most common inconsistency was the number of secondary outcome measures reported (80%). Sixteen trials (15%) reported the primary outcome description inconsistently, and 22 (20%) reported the primary outcome value inconsistently. Thirty-eight trials inconsistently reported the number of individuals with a serious adverse event (SAE); of these, 33 (87%) reported more SAEs in ClinicalTrials.gov. Among the 84 trials that reported SAEs in ClinicalTrials.gov, 11 publications did not mention SAEs, 5 reported them as zero or not occurring, and 21 reported a different number of SAEs. Among 29 trials that reported deaths in ClinicalTrials.gov, 28% differed from the matched publication.
Small sample that included earliest results posted to the database.
Reporting discrepancies between the ClinicalTrials.gov results database and matching publications are common. Which source contains the more accurate account of results is unclear, although ClinicalTrials.gov may provide a more comprehensive description of adverse events than the publication.
Agency for Healthcare Research and Quality.
Hartung DM, Zarin DA, Guise J, et al. Reporting Discrepancies Between the ClinicalTrials.gov Results Database and Peer-Reviewed Publications. Ann Intern Med. 2014;160:477–483. doi: 10.7326/M13-0480
Download citation file:
Published: Ann Intern Med. 2014;160(7):477-483.
Healthcare Delivery and Policy, Research and Reporting Methods.
Copyright © 2019 American College of Physicians. All Rights Reserved.
Print ISSN: 0003-4819 | Online ISSN: 1539-3704
Conditions of Use