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….”.