Why carry out this study?

In COPD, effectiveness of inhaled therapy delivered via dry powder inhalers (DPIs) requires generation of sufficient peak inspiratory flow (PIF), as well as good inhalation technique and medication adherence.

PIFotal is a cross-sectional observational study that will investigate the effects of PIF, inhalation technique and medication adherence on patient-reported outcomes in patients with COPD within a primary care setting.

Here, we report the methodology of the PIFotal COPD study.

What will be learned from the study?

Results from this study will enable better understanding of the relationship between PIF, inhalation technique, medication adherence and health status in DPI users.

In contrast to previous studies, the assessment of PIF and inhalation manoeuvre will be measured objectively for a given inhaler using the In-Check DIAL device.

In contrast to previous large studies, PIFotal will use video recordings with multiple assessors to objectify inhalation technique errors.

Patients manifesting inhalation errors during their visit will receive tailored instruction in correct inhaler technique.

Limitations include the cross-sectional study design, which does not allow the assessment of causality; recall bias associated with self-reported instruments; and no comparison of DPIs versus other inhaler types.

In addition, the study only includes patients with stable COPD and not current exacerbations.