Table 1 HOME BP intervention procedures for prescribers and supporters

Prescriber

Planning medication escalations

At a baseline consultation, prescribers planned three potential consecutive medication escalations which they would initiate if the patient’s average blood pressure was raised for two consecutive months during the trial.

Changing medication in response to recommendations

When patients’ average blood pressure readings were above-target for two consecutive months, prescribers received an automated email recommending they make the next planned medication escalation (Additional file 2).

When patients had a one-off very high or very low reading, the automated email recommended a clinical review.

The patient could email their prescriber via the intervention in the case of raised blood pressure readings or after a recent medication escalation. Prescribers could reply to patients via email using the HOME BP programme.

Notifying patient of medication escalation via remote communication

A template letter was provided for practitioners to send patients, asking them to pick up the prescription.

Supporter

Providing remote support

Supporters were prompted by automated email to send monthly support emails to patients using pre-written templates (Additional file 3). These templates were designed to keep patients motivated to continue self-monitoring their blood pressure and engaging in any healthy lifestyle changes (an optional add-on).

Supporters could also send ad hoc emails to patients. These could be supporter-initiated (e.g. congratulating them on well-controlled readings or asking about a new medication) or patient-initiated (e.g. to respond to emails sent from patients via HOME BP using the ‘Ask the Nurse’ function).

Providing in-person support using the CARE approach

In-person support was designed to be minimal, but patients were offered optional appointments to help learn how to use the blood pressure monitor, and to support them in choosing a healthy lifestyle change.