TY - JOUR
T1 - Poor compliance of clinical trial registration among trials included in systematic reviews
T2 - a cohort study
AU - Lindsley, Kristina
AU - Fusco, Nicole
AU - Teeuw, Hannah
AU - Mooij, Eva
AU - Scholten, Rob
AU - Hooft, Lotty
N1 - Funding Information:
Funding sources: This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. This work was presented, in part, at the Association for Research in Vision and Ophthalmology Annual Meeting (virtual presentation; May 2020) and the Society of Clinical Trials Annual Meeting (virtual presentation; June 2020). Conflicts of interest statement: K.L. is affiliated with Cochrane Netherlands, is a contributing author with the Cochrane Eyes and Vision Group, and was employed by IBM Watson Health during the time period that the study was conducted; however, IBM Watson Health had no role in the concept, design, analysis, interpretation, presentation, or funding of the study. N.F. was employed by IBM Watson Health during the time period that the study was conducted; however, IBM Watson Health had no role in the concept, design, analysis, interpretation, presentation, or funding of the study. H.T.: none known. E.M: none known. R.S. is the former Director of Cochrane Netherlands. L.H. is the Director of Cochrane Netherlands. There are no known financial conflicts of interest. Credit Author Statement: Kristina Lindsley contributed to Conceptualization; Data curation; Formal analysis; Investigation; Methodology; Project administration; Resources; Software; Supervision; Validation; Visualization; Writing ? original draft, editing, and final approval of the submitted manuscript. Nicole Fusco contributed to Data curation; Formal analysis; Investigation; Methodology; Validation; Visualization; Writing ? review, editing, and final approval of the submitted manuscript. Hannah Teeuw contributed to Data curation; Validation; Visualization; Writing ? review, editing, and final approval of the submitted manuscript. va Mooij contributed to Data curation; Validation; Visualization; Writing ? review, editing, and final approval of the submitted manuscript. Rob Scholten contributed to Conceptualization; Methodology; Funding acquisition; Supervision; Writing ? review, editing, and final approval of the submitted manuscript. Lotty Hooft contributed to Conceptualization; Methodology; Funding acquisition; Supervision; Writing ? review, editing, and final approval of the submitted manuscript.
Publisher Copyright:
© 2020 The Authors
PY - 2021/4
Y1 - 2021/4
N2 - OBJECTIVES: The objective of the study was to examine whether clinical trials that have been included in systematic reviews have been registered in clinical trial registers and, when they have, whether results of the trials were included in the clinical trial register.STUDY DESIGN AND SETTING: This study used a sample of 100 systematic reviews published by the Cochrane Musculoskeletal, Oral, Skin and Sensory Network between 2014 and 2019.RESULTS: We identified 2,000 trials (369,778 participants) from a sample of 100 systematic reviews. The median year of trial publication was 2007. Of 1,177 trials published in 2005 or later, a clinical trial registration record was identified for 368 (31%). Of these registered trials, 135 (37%) were registered prospectively and results were posted for 114 (31%); most registered trials evaluated pharmaceutical interventions (62%). Of trials published in the last 10 years, the proportion of registered trials increased to 38% (261 of 682).CONCLUSION: Although some improvement in clinical trial registration has been observed in recent years, the proportion of registered clinical trials included in recently published systematic reviews remains less than desirable. Prospective clinical trial registration provides an essential role in assessing the risk of bias and judging the quality of evidence in systematic reviews of intervention safety and effectiveness.
AB - OBJECTIVES: The objective of the study was to examine whether clinical trials that have been included in systematic reviews have been registered in clinical trial registers and, when they have, whether results of the trials were included in the clinical trial register.STUDY DESIGN AND SETTING: This study used a sample of 100 systematic reviews published by the Cochrane Musculoskeletal, Oral, Skin and Sensory Network between 2014 and 2019.RESULTS: We identified 2,000 trials (369,778 participants) from a sample of 100 systematic reviews. The median year of trial publication was 2007. Of 1,177 trials published in 2005 or later, a clinical trial registration record was identified for 368 (31%). Of these registered trials, 135 (37%) were registered prospectively and results were posted for 114 (31%); most registered trials evaluated pharmaceutical interventions (62%). Of trials published in the last 10 years, the proportion of registered trials increased to 38% (261 of 682).CONCLUSION: Although some improvement in clinical trial registration has been observed in recent years, the proportion of registered clinical trials included in recently published systematic reviews remains less than desirable. Prospective clinical trial registration provides an essential role in assessing the risk of bias and judging the quality of evidence in systematic reviews of intervention safety and effectiveness.
KW - Evidence synthesis
KW - Randomized controlled trial
KW - Systematic review
KW - Trial registration
UR - https://www.scopus.com/pages/publications/85099231861
U2 - 10.1016/j.jclinepi.2020.12.016
DO - 10.1016/j.jclinepi.2020.12.016
M3 - Article
C2 - 33333165
SN - 0895-4356
VL - 132
SP - 79
EP - 87
JO - Journal of Clinical Epidemiology
JF - Journal of Clinical Epidemiology
ER -