Table 4.

Low risk versus high risk of bias results (odds ratios (95% confidence intervals)) for overt gastrointestinal bleeding

Comparison	Low risk of bias result	High risk of bias result*	Subgroup difference (P value)
PPIs v placebo	0.59 (0.45 to 0.76)	0.20 (0.09 to 0.48)	0.02†
H2RAs v placebo	0.34 (0.19 to 0.61)	0.45 (0.23 to 0.88)	0.54
Sucralfate v placebo	3.36 (0.34 to 33.13)	0.52 (0.28 to 0.95)	0.12
PPIs v H2RAs	0.57 (0.27 to 1.23)	0.32 (0.16 to 0.65)	0.28
PPIs v sucralfate	0.31 (0.03 to 3.05)	0.11 (0.01 to 2.20)	0.59
H2RAs v sucralfate	0.46 (0.23 to 0.91)	1.47 (1.01 to 2.15)	0.004†

^*For PPIs versus placebo, studies were at high risk of bias if either allocation sequence concealment or blinding or missing outcome data were at high risk of bias. For other comparisons, studies were at high risk of bias if either allocation sequence concealment or blinding were at high risk of bias.

^†Important difference between low and high risk of bias result, so we used low risk of bias result as best estimate.