Studies comparing multiple devices
| Ref. | Disease | Subjects n | Duration visits | Design | Devices compared | Assessments | Clinical outcomes | Which preferred? | Sponsor |
| [2] | OLD | 100 | 1 | Instruction and handling | 7 devices. All placebos (?) | Technique; 3-category scoring | None | 1) EasibreatheTM* 2) AutohalerTM# | None |
| [3] | COPD | 20 | 1 | Instruction and handling | 7 devices. All placebos (?) | Technique score ×2, device preference ranked | Spirometry | 1) Diskus®¶, 2) pMDI | None |
OLD: obstructive lung disease; COPD: chronic obstructive pulmonary disease; pMDI: pressurised metered-dose inhaler. ?: not clear from published paper; *: manufactured by Ivax, Miami, FL, USA; #: 3M Pharmaceuticals, St Paul, MN, USA; ¶: GlaxoSmithKline, Brentford, UK.