| Study | Reason for exclusion |
|---|---|
| Andres Jacome 2003 | Not an RCT |
| Azouz 2015 | Cross‐over study performed during 1 clinic visit. Participants used 2 different inhaler types in a randomised order before and after normal, and then enhanced training with the IN‐CHECK device. Before‐and‐after data presented only |
| Basheti 2005a | Intervention delivered to pharmacists; focus was pharmacists' knowledge rather than participant outcomes |
| Bosnic‐Anticevich 2010 | Mixed population with asthma and COPD; no disaggregated data presented |
| Compton 2000 | Healthy participants |
| Eakin 2015 | Preliminary observational findings from a complex educational intervention. Primary focus of intervention not inhaler technique |
| Epstein 2001 | Not an RCT |
| Eriksson 1980 | Trial of impact of spacer delivery on bronchodilatation outcomes |
| Fornell 2014 | Primary focus of intervention not inhaler technique |
| Garcia‐Cardenas 2013 | Primary focus of intervention not inhaler technique |
| Grover 2016 | Primary focus of intervention not inhaler technique |
| Hesselink 2004 | Mixed population with asthma and COPD; no disaggregated data presented |
| Hodges 1981 | Trial of impact of spacer delivery on bronchodilatation outcomes |
| Horner 2008 | Primary focus of intervention not inhaler technique |
| Jolly 2012 | Not stated that participants had asthma; likely mixed population with asthma and COPD judging by age and sex of participants |
| Jolly 2015 | Mixed population with asthma and COPD; no disaggregated data |
| Kritikos 2007 | Primary focus of intervention not inhaler technique |
| Lee 2010 | Not an RCT |
| McElnay 1989 | Randomised portion of trial involved healthy volunteers |
| Mulloy 1996 | Primary focus of intervention not inhaler technique |
| NCT01426581 | Mixed population with asthma and COPD; no disaggregated data |
| NCT01456494 | Mixed population with asthma and COPD; no disaggregated data |
| NCT01641211 | Subanalysis of a larger trial investigating a multi‐faceted intervention to improve asthma management in older adults. Primary focus of intervention not inhaler technique |
| NCT02046759 | Primary focus of intervention not inhaler technique |
| NCT02307669 | Primary focus of intervention not inhaler technique |
| NCT02363192 | Primary focus of intervention not inhaler technique |
| NCT02715219 | Primary focus of intervention not inhaler technique |
| Pedersen 1983 | Primary focus of intervention not inhaler technique |
| Poureslami 2016 | Primary focus of intervention not inhaler technique |
| Rachelefsky 1986 | Cross‐over study of spacer drug delivery |
| Reiser 1986 | Cross‐over study primarily assessing impact of spacer delivery on lung function |
| Sandos Dde 2010 | Not an RCT |
| Schacer 2005 | Control group but no mention of random allocation |
| Tuazon 2002 | Primary focus of intervention not inhaler technique |
| Verver 1996 | Mixed population with asthma and COPD; no disaggregated data |
| WIlliams 1983 | Not an RCT ‐ children used as their own controls |
| Wong 1995 | Trial of impact of spacer delivery on bronchodilatation outcomes |
| Yoon 1993 | Primary focus of intervention not inhaler technique |
COPD: chronic obstructive pulmonary disease; RCT: randomised controlled trial.