Fig. 2.

PIFotal study design. Figure produced by the General Practitioners’ Research Institute. Step 1: clinical examination; Step 2: verification of eligibility; Step 3: written informed consent; Step 4: PIF assessment; Step 5: maximal PIF against the resistance of patient’s own device; Step 6: maximal PIF at low resistance; Step 7: fill in three questionnaires (Clinical COPD Questionnaire, COPD Assessment Test and Test of Adherence to Inhalers); Step 8: inhalation technique will be video-recorded using usual medication; Step 9: patients receive tailored inhalation instructions based on the inhalation errors. PIF peak inspiratory flow