Ref (type)	Population	Outcome, Interventions	Results and statistical analysis	Effect size	Favours
Quality of life
[22] Systematic review	1831 people with COPD 3 RCTs in this analysis	Mean change in St George's Respiratory Questionnaire (SGRQ) 6 to 12 months with tiotropium with placebo Absolute numbers not reported	WMD –3.35 95% CI –4.54 to –2.16 P = 0.0001	Effect size not calculated	tiotropium
[24] RCT	555 outpatients aged at least 40 years with COPD	Mean change in SGRQ 9 months –8.5 units with tiotropium 18 micrograms once daily –4.3 units with placebo	P <0.05	Effect size not calculated	tiotropium