Trial and error: challenges conducting pragmatic trials in general practice

Wallis and Elley share their experience and lessons from the SPACE trial (Safer Prescribing And Care for the Elderly) in the hope that others might avoid some of the pitfall. SPACE was conducted in New Zealand general practice where there is no established infrastructure supporting practice-based research. SPACE was a pragmatic trial testing an intervention to support safer prescribing. Unfortunately, soon after securing funding for the trial, a non-trial quality improvement (Ql) initiative was introduced in the same region, targeting the same prescribing topic. This reduced the pool of practices for recruitment (we excluded participating practices), introduced confounding by increasing awareness of the prescribing issue, and since some trial practices joined the initiative during follow up, contaminated their results.