Table 2 General characteristics of the randomized controlled trials (RCTs) related to the clinical research questions (n = 273)

Trial characteristics

Study design

 Single-centre

183 (67 %)

 Multicentre

60 (22 %)

 Not reported

30 (11 %)

Location

 Europe

106 (39 %)

 North America

80 (29 %)

 Asia

78 (29 %)

 Australia and New Zealand

9 (3 %)

Funding

 Public

96 (35 %)

 Private

49 (18 %)

 Not reported

128 (47 %)

Year of publication

 2000–2004

46 (17 %)

 2005–2009

112 (41 %)

 2010–2013

115 (42 %)

Journal of publication characteristics

Type of journal

 Specialized

260 (95 %)

 Generalist

13 (5 %)

Top 10 impact factor of each specialty

 No

156 (57 %)

 Yes

117 (43 %)

Journal data sharing policies

 No policy

241 (88 %)

 Incentive measures

24 (9 %)

 Mandatory

8 (3 %)