Table 2

Trial characteristics of the comparisons

Trial characteristicsTrials blinded for ~ Trials unblinded for ~ 
Participants
Funding sources
  Industry41 (73.2%)22 (84.6%)
  Academic12 (21.4%)3 (11.5%)
  Others3 (5.4%)1 (3.9%)
Year of publication
  ~ 200000
  2001 ~ 201024 (42.9%)19 (73.1%)
  2011 ~ 202032 (57.1%)7 (26.9%)
Region
  Europe and North America10 (19.6%)6 (25.0%)
  Multiple countries27 (52.9%)16 (66.7%)
  Others14 (27.5%)2 (8.3%)
Sample size
  Less than 50037 (66.1%)10 (38.5%)
  500 and more19 (33.9%)16 (61.54%)
Health care providers
Funding sources
  Industry42 (77.8%)24 (88.9%)
  Academic8 (14.8%)2 (7.4%)
  Others4 (7.4%)1 (3.7%)
Year of publication
  ~ 200000
  2001 ~ 201024 (44.4%)20 (74.1%)
  2011 ~ 202030 (55.6%)7 (25.9%)
Region
  Europe and North America5 (20.8%)6 (12.5%)
  Multiple countries17 (70.8%)28 (58.3%)
  Others2 (8.3%)14 (29.2%)
Sample size
  Less than 50011 (40.7%)34 (63.0%)
  500 and more16 (59.3%)20 (37.0%)
Outcome assessors
Funding sources
  Industry498 (93.4%)305 (93.3%)
  Academic28 (5.3%)6 (1.8%)
  Others7 (1.3%)16 (4.9%)
Year of publication
  ~ 20002 (0.4%)1 (0.3%)
  2001 ~ 2010125 (23.5%)69 (21.1%)
  2011 ~ 2020406 (76.2%)257 (78.6%)
Region
  Europe and North America114 (21.6%)47 (15.1%)
  Multiple countries335 (63.6%)248 (79.5%)
  Others78 (14.8%)39 (12.5%)
Sample size
  Less than 500411 (77.1%)214 (65.4%)
  500 and more122 (22.9%)113 (34.6%)
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