Table 1.

Results of Medline search and selection of randomised controlled trials in meta-analyses. Figures are numbers of trials

	Effectiveness of drug v placebo			Rate of pneumonia
	Ranitidine (analysis A)	Sucralfate (analysis B)		Ranitidine v placebo (analysis C)	Sucralfate v placebo (analysis D)	Ranitidine v sucralfate (analysis E)
Identified and screened studies	51	46		59	35	11
Studies excluded	45*	42*		56*	33*	3*
Potentially relevant trials for inclusion	6	4		3	2	8
Studies excluded	124†	316-18†		0	0	0
Trials included	511-15	111		312 13 15	217 18	83 19-26

^*Studies were excluded because they did not compare treatment options considered by meta-analysis in question (A=16; B=18, C=12; D=14; E=1) or because objective of trial was not prophylaxis of stress ulcer (A=29; B=23, C=44; D=19; E=1) or because they duplicated study already included in meta-analysis question (A=0; B=1, C=0; D=0; E=1). 

^†Studies excluded because end point of bleeding did not meet definition of “clinically important bleeding” according to Cook et al.²