Elsevier

Journal of Clinical Epidemiology

Volume 115, November 2019, Pages 37-45
Journal of Clinical Epidemiology

Original Article
Result dissemination from clinical trials conducted at German university medical centers was delayed and incomplete

https://doi.org/10.1016/j.jclinepi.2019.06.002Get rights and content

Highlights

  • This study broadened the scope and methods for trial tracking and further developed the interactive online presentation of publication rates and benchmarks for individual university medical centers (UMCs). We applied these innovative tracking methods to benchmark all 36 German UMCs. The user can modify the benchmarking by changing different tracking variables such as time to publication, type of clinical trial, role of UMC, publication format, and many more.

  • Our study revealed higher publication rates as former tracking studies, especially when adding searches in general internet search engines such as Google Scholar and when giving more time (up to 5+ years) to follow-up, showing that these choices do affect the tracking results and benchmarks substantially.

  • Regarding the WHO definition for “timely publication,” that is, publication in a peer-reviewed journal 2 years after trial completion, the publication rates across all German UMCs varied from 20% to 64%. Five years after trial completion, the rates varied from 43% to 90%.

Abstract

Objectives

Timely and comprehensive reporting of clinical trial results builds the backbone of evidence-based medicine and responsible research. The proportion of timely disseminated trial results can inform alternative national and international benchmarking of university medical centers (UMCs).

Study Design and Setting

For all German UMCs, we tracked all registered trials completed between 2009 and 2013. The results and an interactive website benchmark German UMCs regarding their performance in result dissemination.

Results

We identified and tracked 2,132 clinical trials. For 1,509 trials, one of the German UMCs took the academic lead. Of these 1,509 “lead trials,” 39% published their results (mostly via journal publications) in a timely manner (<24 months after completion). More than 6 years after study completion, 26% of all eligible lead trials still had not disseminated results.

Conclusion

Despite substantial attention from many stakeholders to the topic, there is still a strong delay or even absence of result dissemination for many trials. German UMCs have several opportunities to improve this situation. Further research should evaluate whether and how a transparent benchmarking of UMC performance in result dissemination helps to increase value and reduce waste in medical research.

Section snippets

Background

The results of clinical trials build the backbone of evidence-based medicine. They inform clinical decision-making [1] and health technology assessment [2], [3]. They also inform decision-making within ongoing trials and decision-making related to the design, review, and funding of new trials [4]. Nondissemination or delayed dissemination of trial results negatively affects all of these decision-making processes [5], [6], [7], [8]. For 3 decades, studies investigated and criticized this

Methods

The protocol for this project, including all methodological details for sampling and following up clinical trials for data extraction, and statistical analyses were preregistered with the Open Science Framework (OSF) and continuously updated for amendments (https://osf.io/fh426/). In the following sections, we summarize the methods.

Demographic data

We identified 2,132 clinical trials via clinicaltrial.gov (n = 1,905) and DRKS (n = 227) that (1) recruited trial participants from at least one German UMC and (2) had their PCD (last visit of last patient for a primary outcome measure) between 2009 and 2013. These trials included 506,876 anticipated participants.

Altogether, 71% (n = 1,457) of all trials were counted as lead trial for one of the corresponding German UMCs. Of these 1,457 lead trials, 502 (35%) investigated drugs and 266 (18%)

Discussion

In this study, we demonstrate that only 39% of all registered clinical trials conducted at one of the 36 German UMCs published their results in a timely manner within 24 months after the trial's CD. This rate further decreases to 26% when applying standard search strategies. Six years after the CD and with the most extensive search strategies, 26% of all trials still remain unpublished.

For the following reasons, this high proportion of delayed or omitted result dissemination is unethical and a

CRediT authorship contribution statement

Susanne Wieschowski: Methodology, Formal analysis, Writing - original draft, Writing - review & editing. Nico Riedel: Software, Formal analysis, Data curation, Writing - original draft, Writing - review & editing. Katharina Wollmann: Formal analysis, Writing - review & editing. Hannes Kahrass: Formal analysis, Writing - review & editing. Stephanie Müller-Ohlraun: Formal analysis, Writing - review & editing. Christopher Schürmann: Formal analysis, Writing - review & editing. Sean Kelley:

Acknowledgments

Intramural funding was obtained for this study. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

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    Conflict of interest: All authors are affiliated with a German UMC in Berlin, Hannover, or Freiburg. No further conflicts of interest exist.

    Software availability: The R script used as part of this study is available from https://doi.org/10.17605/OSF.IO/FH426. Archived source code at time of publication: https://doi.org/10.17605/OSF.IO/FH426. License: MIT License.

    Data availability: All data underlying the results are available as part of the article and at OSF: Data set 1: IntoValue. https://doi.org/10.17605/OSF.IO/FH426. The data are available under a CC0 license. No additional source data are required.

    1

    These authors contributed equally to this work.

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