Skip to main content

Table 5 Multi-predictor model of high impact factor (> 5)

From: Journal impact factor, trial effect size, and methodological quality appear scantly related: a systematic review and meta-analysis

Potential predictorsOdds ratio (95% CI)p value
Effect size (relative risk) 0.43
 0–0.52.48 (0.61, 10.1) 
 0.5–1Ref 
 > 10.79 (0.32, 1.91) 
Statistically significant1.50 (0.47, 4.84)0.50
Multicenter1.34 (0.68, 2.62)0.39
Medical domain 0.11
 Medicine4.25 (0.82, 22.2) 
 Obstetric0.68 (0.06, 8.03) 
 Pediatrics0.99 (0.17, 5.71) 
 SurgeryRef 
Industry funding1.61 (0.71, 3.67)0.26
Peer review funding0.99 (0.38, 2.57)0.99
Random sequence1.58 (0.63, 3.93)0.33
Allocation concealment, clearly adequate (A) or not (BCD)0.53 (0.26, 1.08)0.08
Double-blind0.88 (0.21, 3.64)0.86
Analysis as randomized 0.65
 Unclear0.60 (0.17, 2.09) 
 As treated0.57 (0.18, 1.80) 
 As randomizedRef 
Sample size (every 10 increase)1.012 (0.997, 1.027)0.12
Country 0.84
 Canada/USA2.60 (0.11, 63.0) 
 Europe1.54 (0.06, 36.6) 
 AsiaRef 
 Other2.42 (0.07, 84.7) 
  1. CI confidence interval