Ref (type)	Population	Outcome, Interventions	Results and statistical analysis	Effect size	Favours
Failure to respond to treatment
Systematic review	Adults with advanced illness, in chronic non-malignant pain, having an orthopaedic procedure, or part of a methadone maintenance programme, based in primary, secondary, and/or tertiary care 6 RCTs in this analysis	Failure to respond to treatment (response defined as defecation within 1 minute of infusion [1 RCT], 3 or more rescue-free bowel movements [BM] per week [3 RCTs], rescue-free BM within 24 hours of dose [1 RCT] or BM within 4 hours of first dose) 533/1095 (49%) with methylnaltrexone 332/515 (65%) with placebo	RR 0.67 95% CI 0.54 to 0.84 P = 0.0004 NNT 3 95% CI 2 to 10 Significant heterogeneity in this analysis (I2 = 72%, P for heterogeneity 0.003; see Further information on studies)	Small effect size	methylnaltrexone