Describing drivers of and barriers to persistence with tiotropium in patients with chronic obstructive pulmonary disease: a mixed-methods approach.

Objective: To understand the factors influencing persistence with tiotropium in patients with chronic obstructive pulmonary disease (COPD).

Methods: Patients classified as 'persistent' or 'non-persistent' with tiotropium were identified from pharmacy dispensing records. Patients were compared for health status, beliefs and behaviours using data from questionnaires and interviews.