Ref (type)	Population	Outcome, Interventions	Results and statistical analysis	Effect size	Favours
Adverse effects
[15] RCT	Number of people not reported	Dry mouth with ipratropium with placebo Absolute results not reported	P <0.05	Effect size not calculated	placebo
[17] RCT 3-armed trial	405 people	Adverse effects affecting the ear, nose, and throat 12 weeks 58/138 (42%) with ipratropium (36 micrograms 4 times daily) 39/135 (29%) with placebo	P = 0.031 (ipratropium v placebo)	Effect size not calculated	placebo
[18] RCT 3-armed trial	780 people	Adverse effects (any) with ipratropium (40 micrograms 4 times daily) with placebo Absolute results not reported
[16] [19] RCT 3-armed trial	459 people in total in the two RCTs	Adverse effects (any) with ipratropium with placebo Absolute results not reported	Significance not assessed in either RCT