Frequency of Use of Clinical Trials Registries in Systematic Reviews and Meta-Analyses in Primary Care Journals

Authors

  • Julie Dionne Oklahoma State University Center for Health Sciences
  • Lora Cotton Oklahoma State University Center for Health Sciences
  • Christopher Thurman Oklahoma State University Center for Health Sciences
  • Matt Vassar Oklahoma State University Center for Health Sciences

Keywords:

clinical trials registry, publication bias, systematic review, meta-analysis

Abstract

Abstract Objective: To evaluate the use of clinical trials registries in published primary care systematic reviews and meta-analyses. Background: Systematic reviews and meta-analyses in primary care medicine that do not report searching for unpublished data may be prone to publication bias. This source of bias occurs when systematic review evidence is based solely on a published body of literature and does not account for studies where results failed to achieve statistical significance and were therefore less likely to be published. One method to address publication bias is to perform a comprehensive search that includes the use of clinical trials registry searches in systematic reviews and meta-analyses published in the top 10 primary care journals over the past 8 years. Methods: Systematic reviews and meta-analyses were retrieved from the top 10 primary care medicine journals published between January 1st, 2008 and December 31st, 2015 using a highly sensitive search string designed in collaboration with a medical librarian on staff at the Oklahoma State University Center for Health Sciences. We performed a meta-epidemiological study to evaluate the frequency of clinical trials registry searches reported in these systematic reviews and meta-analyses and to evaluate these searches over time. Results: A total of 205 articles retrieved from PubMed were included for analysis. We found that of the 205 systematic reviews and meta-analyses, only 8.3% (17/205) searched clinical trials registries for unpublished data. Conclusions: A large portion of systematic reviews and meta-analyses in primary care literature do not search clinical trials registries for unpublished data. Omission of unpublished data from analysis may lead to publication bias and reduced validity of the true effect sizes of interventions.

References

References

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Published

2017-10-16

Issue

Vol. 1 No. 1 (2017)

Section

Biomedical Sciences

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