The Journal Impact Factor as a Predictor of Trial Quality and Outcomes: Cohort Study of Hepatobiliary Randomized Clinical Trials

Gluud, Lise L.; Sørensen, Thorkild I. A.; Gøtzsche, Peter C.; Gluud, Christian
November 2005
American Journal of Gastroenterology;Nov2005, Vol. 100 Issue 11, p2431
Academic Journal
OBJECTIVES: To examine the association between the impact factor and characteristics of hepatobiliary randomized clinical trials. METHODS: A cohort study of 530 hepatobiliary randomized clinical trials was performed. The journal impact factor was extracted from Science Citation Index. For each trial, we extracted the sample size, the quality of randomization and blinding methods, and the statistical significance of the primary outcome measure. RESULTS: The median sample size was 45 participants (interquartile range 25–88). The allocation sequence generation was adequate in 273 trials (52%). Allocation concealment was adequate in 178 trials (34%). The primary outcome measure was statistically significant in 374 (71%) trials. Nonparametric analyses for trend indicated that the impact factor was significantly associated with the sample size ( p < 0.01) and the proportion of trials with adequate allocation sequence generation ( p < 0.01) or allocation concealment ( p= 0.02). The impact factor was not significantly associated with the study outcome ( p= 0.28). CONCLUSIONS: The present study supports the use of the impact factor as a rough quality indicator. However, even trials in high impact journals may be small or may have inadequate quality. Critical appraisal of individual trials is always necessary, irrespective of the place of publication.


Related Articles

  • The nature of clinical trials in nephrology.  // Kidney International;Nov1992, Vol. 42 Issue 5, p1061 

    The article reflects the opinion of the author on the manner in which cooperative trials might be organized in relation to nephritides. The author addressed glomerulopathies as an example for clinical trials, not because it is a major cause of renal morbidity and mortality, but because the...

  • Clinical Trials: Minimising source data queries to streamline endpoint adjudication in a large multi-national trial.  // Trials;2011, Vol. 12 Issue 1, p112 

    The article presents a multi-national study reviewing trial data submitted to a Clinical Endpoint Committee in Great Britain for adjudication in order to identify areas that could be improved for future clinical trials. The study revealed that the implementation of some simple measures will be...

  • Abstracts.  // Kidney International;Aug1984, Vol. 26 Issue 2, p228 

    Presents several abstracts on nephrology. "Macrophages, Fibrin, and Human Renal Allograft Rejection," by W. W. Hancock, F. R. Rickles and R. C. Atkins; "Controlled Clinical Trial of Cyclosporin A in Cadaveric Donor Renal Transplantation," by A. G. R. Sheil, B. M. Hall and D. J. Tiller; "Effect...

  • Publication Guidelines for Improvement Studies in Health Care: Evolution of the SQUIRE Project. Davidoff, Frank; Batalden, Paul; Stevens, David; Ogrinc, Greg; Mooney, Susan // Annals of Internal Medicine;11/4/2008, Vol. 149 Issue 9, p670 

    In 2005, draft guidelines were published for reporting studies of quality improvement as the initial step in a consensus process for development of a more definitive version. The current article contains the revised version, which we refer to as Standards for QUality Improvement Reporting...

  • Oncology survey finds optimism, cost concerns.  // Clinical Trials Administrator;Mar2010, Vol. 8 Issue 3, p33 

    The article discusses a survey sponsored by the U.S. Oncology which revealed that optimism was found for personalized medicine in clinical trials. The KJT Group conducted interviews of 299 oncologists, hematologists and clinical trial practitioners. Findings of the survey indicated that 57.5% of...

  • The promise of risk-based allocation trials in assessing new treatments. Mosteller, Frederick // American Journal of Public Health;May96, Vol. 86 Issue 5, p622 

    The author comments on the promise of risk-based allocation trials in assessing new treatments. He analyzes the article "Clinical and Prophylactic Trials With Assured New Treatment for Those at Greater Risk: A Design Proposal," by M. O. Finkelstein, B. Levin and H. Robbins. He describes the...

  • Trabeculectomy, shunt use yield similar outcomes. Groves, Nancy; Minckler, Donald S. // Ophthalmology Times;4/15/2007, Vol. 32 Issue 8, p1 

    The article reports on the clinical outcomes of trabeculectomy in the U.S. A systematic, evidence-based review of prior randomized clinical trials (RCTs) of aqueous shunts have found no clear evidence that long-term clinical outcomes of trabeculectomy differ substantially from those of aqueous...

  • Transition from congress abstract to full publication for clinical trials presented at laser meetings. Akbari-Kamrani, Marjan; Shakiba, Behnam; Parsian, Sana // Lasers in Medical Science;Sep2008, Vol. 23 Issue 3, p295 

    The present study aims to identify (1) what proportion of abstracts of clinical trials presented at The American Society for Laser Medicine and Surgery (ASLMS) annual meetings are published as full reports, (2) time to publication, and (3) factors that may predict the publication of research in...

  • Clinical Trials in New Europe. DOIG, AL // Bio-IT World;Jan2009, Vol. 8 Issue 1, p13 

    The article presents an outlook for clinical trials in New Europe for 2009. The collapse of the Soviet Union is cited as one of the major factors which contributed to the emergence of new opportunity for clinical trials in Europe. An overview of the report from Insight Pharma Reports entitled...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics