Attribution of non-ClinicalTrials.gov registries among WHO International Clinical Trials Registry Platform-registered trials from 2014 to 2018: A protocol for a meta-epidemiological study
Author and article information
Abstract
Background. The attribution of non-ClinicalTrials.gov registries among registered trials of the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) had increased until 2013. However, the attribution after 2013 is unknown. Moreover, no study has investigated the usage of non-ClinicalTrials.gov registries after 2015 or compared the characteristics of trials under non-ClinicalTrials.gov and ClinicalTrials.gov registries. Methods. This will be a meta-epidemiological study. It will include all trials registered on the ICTRP from January 1, 2014, to December 31, 2018. First, we will describe the total attribution of non-ClinicalTrials.gov registries among the ICTRP-registered trials for each year and each registry worldwide. Second, we will compare the recruitment status, target sample size, study type, countries, retrospective registration, funding, and study phase of the trials on ClinicalTrials.gov and other registries from 2014 to 2018. Third, we will report on the distribution of primary registries of trials from the top five countries in order of the quantity of registered trials on the ICTRP. We will separately report the results from interventional and other studies. Inclusion criteria for interventional studies will be studies that include the word “intervention” or “interventional” in “study type” of the data set. Other studies will refer to studies other than interventional studies such as cohort, case-control, and cross-sectional studies. Ethics & Dissemination. Ethics approval is not required for this study. This protocol has been registered in the University Hospital Medical Information Network Clinical Trials Registry (UMIN-CTR). The findings will be published in a peer-reviewed journal and may be presented at conferences. Trial Registration Number. UMIN000034401
Cite this as
2019. Attribution of non-ClinicalTrials.gov registries among WHO International Clinical Trials Registry Platform-registered trials from 2014 to 2018: A protocol for a meta-epidemiological study. PeerJ Preprints 7:e27298v2 https://doi.org/10.7287/peerj.preprints.27298v2Author comment
We changed "prospective registration" into "retrospective registration" in Methods of ABSTRACT.
We added the following sentences in ABSTRACT: "We will separately report….. Inclusion criteria for….. Other studies will refer…..."
We added the following sentences in introduction: "We will investigate not only….. Non-interventional studies registered on ClinicalTrials.gov are…..."
We added the following sentences in Study Objectives of introduction as follows: "We will separately report the results from interventional and other studies."
We added the following sentences in “Types of Studies to be Included” of Materials & Methods: “We will divide trials into interventional studies and other studies. The inclusion criteria for interventional studies will be studies that include the word “intervention” or “interventional” in “study type” of the data set. Other studies will refer to studies other than interventional studies such as cohort, case-control, and cross-sectional studies (Boccia et al., 2016).”
We changed “in February 1, 2019” into “on March 2019” in Search Methods of Materials & Methods.
We added “Secondary_sponsors” and “Bridged_type” in “About the Data Set” of Materials & Methods.
We revised the sentences in Data Analysis of Materials & Methods as follows: “Third, the study will report on the recruitment status, target sample size, study type, countries, retrospective registration (Yes, No), funding (Yes, No), and study phase of the trials on ClinicalTrials.gov and other registries between 2014 and 2018. We will record a “Yes” for retrospective registration if retrospective_flag is found to be “1,” and a “No” if retrospective_flag is found to be “NULL” or unclear.”
We added sensitivity analysis in Materials & Methods as follows: “We will perform….”.
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Additional Information
Competing Interests
Masahiro Banno has received speaker honoraria from Dainippon Sumitomo and travel fees from Yoshitomi Pharmaceutical Industries Ltd. The other authors have no competing interests to declare.
Author Contributions
Masahiro Banno conceived and designed the experiments, performed the experiments, analyzed the data, contributed reagents/materials/analysis tools, prepared figures and/or tables, authored or reviewed drafts of the paper, approved the final draft.
Yasushi Tsujimoto conceived and designed the experiments, performed the experiments, analyzed the data, contributed reagents/materials/analysis tools, authored or reviewed drafts of the paper, approved the final draft.
Yuki Kataoka conceived and designed the experiments, performed the experiments, analyzed the data, contributed reagents/materials/analysis tools, authored or reviewed drafts of the paper, approved the final draft.
Data Deposition
The following information was supplied regarding data availability:
The protocol has no data because we do not analyse data at the moment.
Funding
This work was supported by the Department of Respiratory Medicine, Hyogo Prefectural Amagasaki General Medical Center, and the Nagoya University Academy of Psychiatry. Self-funding was also involved. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
