It was a randomised intervention study, with before-and-after outcome measures and a control group, in patients who had an active long-term prescription for PPIs at high doses for at least 6 months.

The intervention consisted of sending patients an informative letter by post, in which their doctor invited them to seek an appointment for a medication review. Control group patients did not receive such a letter, and they were treated as usual (their doctors received a list of identifiers of patients on high doses).

The main outcome variable was the number of active prescriptions of each PPI dose (high dose/standard dose/treatment cessation) at 6 months after the intervention.

Inclusion Criteria:

• Patients under the care of our organisation who in May 2017 had an active long-term prescription for PPIs at high doses for at least 6 months.

Exclusion Criteria:

• Patients whose GPs declined to participate