Table 2.

Descriptive overview of the sample of trials included [Data sources: MEDLINE (N = 4337) or Web of Science (N = 4241)].

Item	N (%)
Year of publication (N = 4337)
2014	694 (16%)
2015	816 (18.8%)
2016	778 (17.9%)
2017	872 (20.1%)
2018	866 (20%)
2019 ^*	311 (7.2%)
Top 10 Research Areas according to Web of Science ^** (N = 4241)
General & Internal Medicine	1012 (23.9%)
Public, Environmental & Occupational Health	577 (13.6%)
Health Care Sciences & Services	365 (8.6%)
Psychiatry	318 (7.5%)
Psychology	244 (5.8%)
Pediatrics	195 (4.6%)
Science Technology Other topics	173 (4.1%)
Cardiovascular systems & Cardiology	172 (4.1%)
Oncology	170 (4%)
Infectious Diseases	165 (3.9%)
Top 10 Countries of Author Affiliations ^*** (N = 4241)
USA	1779 (41.9%)
UK	1086 (25.6%)
Australia	452 (10.7%)
Netherlands	400 (9.4%)
Canada	295 (7%)
China	266 (6.2%)
Germany	220 (5.2%)
France	156 (3.7%)
Denmark	148 (3.5%)
Spain	145 (3.4%)
Top 10 Funders (N = 4241)^Ψ
United States Department of Health & Human Services	949 (22.4%)
National Institutes of Health (USA)	871 (20.5%)
National Institutes for Health Research (UK)	336 (7.9%)
Medical Research Council (UK)	191 (4.5%)
NIH National Cancer Institute (NCI)	173 (4.1%)
National Health and Medical Research Council of Australia	166 (3.9%)
NIH National Center for Advancing Translational Sciences (NCATS)	155 (3.7%)
NIH National Heart Lung Blood Institute (NHLBI)	133 (3.1%)
NIH National Institute of Mental Health (NIMH)	130 (3.1%)
Netherlands Organization for Health Research and Development	114 (2.7%)

Search conducted April 3, 2019.

^**

Articles could be assigned multiple Research Areas, so does not sum to 4241.

^***

Derived from author affiliation information for all listed authors. Authors could have multiple affiliations, hence does not sum to 4241.

^Ψ