Background After the summer break, asthma exacerbation rates peak in school-aged children. Researchers have found there is a decrease in prescription collection during August, followed by an increase in unscheduled visits with healthcare providers. An investigation into this was conducted in a cluster randomized controlled trial (PLEASANT) where sending a reminder letter to parents of asthmatic children during summer vacation resulted in 30% more prescriptions collected in August and a 20% decrease in unscheduled care visits from September to December. Moreover, this intervention resulted in an estimated cost saving of £36.07 per patient per year as a result of this intervention.

Objective To conduct a randomised trial to determine if providing GP practices with access to an evidence-based intervention leads to its implementation.

Design A pragmatic cluster randomised trial using routine data. The Clinical Practice Research Datalink (CPRD) was used to send the intervention and to collect the data needed for the study.

Participants 1389 GP practices in England, with 694 in the intervention group and 695 in the control group.

Intervention arm Received a letter in June 2021 containing the findings of the PLEASANT study and recommendations from CPRD. It was sent via postal mail and email to the asthma lead or practice manager.

Control arm Usual care

Randomisation GP practices were stratified by practice size and randomly assigned to intervention or control.

Main outcome Proportion of children with asthma who have a prescription for an asthma preventer medication in August and September 2021.

Results: In progress.