Fig. 2
From: Peak expiratory flow as an endpoint for clinical trials in asthma: a comparison with FEV1
Correlation analysis results between pre-dose FEV1 and pre-dose PEF, measured either under supervision in the clinic or unsupervised at home, at the time of primary efficacy evaluation. Phase III trials with tiotropium Respimat® in patients aged 12–75 years with persistent asthma – all patients analysed for efficacy. (a) In-clinic pre-dose FEV1 vs. in-clinic pre-dose PEF; (b) in-clinic pre-dose FEV1 vs. home-measured pre-dose FEV1a; (c) in-clinic pre-dose PEF vs. home-measured pre-dose PEFb. aHome-measured pre-dose FEV1: weekly mean morning FEV1 in the trials with morning dosing (PrimoTinA-asthma®) and weekly mean evening FEV1 in the trials with evening dosing (RubaTinA-asthma®, PensieTinA-asthma®, GraziaTinA-asthma®, MezzoTinA-asthma®, CadenTinA-asthma®), measured with AM device. bHome-measured pre-dose PEF: weekly mean morning PEF in the trials with morning dosing (PrimoTinA-asthma®) and weekly mean evening PEF in the trials with evening dosing (RubaTinA-asthma®, PensieTinA-asthma®, GraziaTinA-asthma®, MezzoTinA-asthma®, CadenTinA-asthma®), measured with AM device. PEF was not measured at clinic visits in the PrimoTinA-asthma® study. FEV1 = forced expiratory volume in one second; PEF = peak expiratory flow