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Table 2 Exclusion rates by trial characteristics

From: Exclusion rates in randomized controlled trials of treatments for physical conditions: a systematic review

Variable (number of trials)Unadjusted coefficient (95% CI)aP valueAdjusted coefficient (95% CI)aP value
Condition
 HIV infection (n = 32)Reference Reference 
 Cancer (n = 24)15.6 (5.0 to 26.2)< 0.00120.4 (8.8 to 32.0)< 0.001
 Cardiovascular (n = 81)31.8 (23.8 to 39.7)0.00334.0 (24.0 to 44.0)< 0.001
 Respiratory (n = 78)36.6 (27.8 to 45.3)< 0.00143.1 (31.9 to 54.2)< 0.001
 Rheumatoid arthritis (n = 51)44.6 (36.9 to 52.2)< 0.00143.9 (33.4 to 54.4)< 0.001
 Diabetes (n = 16)42.4 (28.2 to 56.7)< 0.00146.8 (31.1 to 62.6)< 0.001
 Other conditions (n = 23)19.5 (9.2 to 29.8)< 0.00125.0 (12.2 to 37.8)< 0.001
Trial funding sourceb
 Public (n = 75)Reference Reference 
 Industry (n = 203)15.7 (9.6 to 21.7)< 0.001−4.7 (−11.0 to 1.6)0.1
Comparison clinical population setting
 Primary care (n = 198)Reference Reference 
 Specialist care (n = 107)−6.2 (−11.7 to −0.6)0.03−3.0 (−9.0 to 3.0)0.3
Year of trial publication
 1994–1999 (n = 81)Reference Reference 
 2000–2003 (n = 78)−4.0 (−11.4 to 3.3)0.28−4.7 (−10.8 to 1.4)0.1
 2004–2011 (n = 75)− 1.1 (−8.6 to 6.3)0.76− 6.2 (−13.1 to 0.7)0.08
 2012–2018 (n = 71)−0.3 (−7.4 to 7.9)0.95−6.5 (−13.8 to 0.7)0.08
Risk of bias
 Low (n = 126)Reference Reference 
 High/Unclear (n = 179)17.2 (12.2 to 22.2)< 0.0019.2 (3.5 to 14.8)0.002
  1. Abbreviations: CI confidence interval, HIV human immunodeficiency virus
  2. a The coefficients are interpreted as the percentage point difference in exclusion in each category compared with the reference
  3. b Twenty-seven trials did not report funding source