Document Detail

Randomized trials published in higher vs. lower impact journals differ in design, conduct, and analysis.
MedLine Citation:
PMID:  23347852     Owner:  NLM     Status:  MEDLINE    
OBJECTIVE: To compare methodological characteristics of randomized controlled trials (RCTs) published in higher vs. lower impact Core Clinical Journals.
STUDY DESIGN AND SETTING: We searched MEDLINE for RCTs published in 2007 in Core Clinical Journals. We randomly sampled 1,140 study reports in a 1:1 ratio in higher (five general medicine journals with the highest total citations in 2007) and lower impact journals.
RESULTS: Four hundred sixty-nine RCTs proved eligible: 219 in higher and 250 in lower impact journals. RCTs in higher vs. lower impact journals had larger sample sizes (median, 285 vs. 39), were more likely to receive industry funding (53% vs. 28%), declare concealment of allocation (66% vs. 36%), declare blinding of health care providers (53% vs. 41%) and outcome adjudicators (72% vs. 54%), report a patient-important primary outcome (69% vs. 50%), report subgroup analyses (64% vs. 26%), prespecify subgroup hypotheses (42% vs. 20%), and report a test for interaction (54% vs. 27%); P < 0.05 for all differences.
CONCLUSION: RCTs published in higher impact journals were more likely to report methodological safeguards against bias and patient-important outcomes than those published in lower impact journals. However, sufficient limitations remain such that publication in a higher impact journal does not ensure low risk of bias.
Malgorzata M Bala; Elie A Akl; Xin Sun; Dirk Bassler; Dominik Mertz; Filip Mejza; Per Olav Vandvik; German Malaga; Bradley C Johnston; Philipp Dahm; Pablo Alonso-Coello; Natalia Diaz-Granados; Sadeesh K Srinathan; Basil Hassouneh; Matthias Briel; Jason W Busse; John J You; Stephen D Walter; Douglas G Altman; Gordon H Guyatt
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Journal of clinical epidemiology     Volume:  66     ISSN:  1878-5921     ISO Abbreviation:  J Clin Epidemiol     Publication Date:  2013 Mar 
Date Detail:
Created Date:  2013-01-25     Completed Date:  2013-04-05     Revised Date:  2014-02-20    
Medline Journal Info:
Nlm Unique ID:  8801383     Medline TA:  J Clin Epidemiol     Country:  United States    
Other Details:
Languages:  eng     Pagination:  286-95     Citation Subset:  IM    
Copyright Information:
Copyright © 2013 Elsevier Inc. All rights reserved.
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MeSH Terms
Bias (Epidemiology)
Data Interpretation, Statistical
Journal Impact Factor*
Periodicals as Topic / standards*,  statistics & numerical data
Randomized Controlled Trials as Topic / methods,  standards*
Research Design / standards
Sample Size
Grant Support
MR/J004871/1//Medical Research Council; //Canadian Institutes of Health Research

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