Costing the participation of general practice in a pilot randomised controlled trial to increase attendance at diabetic retinopathy screening

Problem

Research participation by healthcare providers is critical to the conduct of research and translation of evidence into practice. However, GPs report lack of time, capacity, and the risk of hindering patient flow as inhibiting factors. Nonetheless, the economic cost to general practice of participating in research is rarely investigated or reported.

Approach

We have estimated the economic cost of participating in the development and implementation of an intervention to increase attendance at diabetic retinopathy screening from a general practice perspective. In a pilot RCT, eight practices were randomly assigned to either intervention or waitlist control. The intervention, delivered over 6 months, comprised (i) audit of patients with diabetes to identify non-attenders of DRS, (ii) addition of electronic prompts to patient records, (iii) delivery of GP-endorsed reminders and information leaflets to eligible patients. Four intervention components were costed: participation in intervention briefing (human resources), intervention delivery (human resources), intervention delivery (consumables), and contact with the research team (human resources). Data were collected at intervention briefing and during research phone calls with practices to establish the number of eligible patients, profession of staff delivering the intervention, time taken to deliver, and consumables required. Resources were valued in line with the Health Information and Quality Authority’s (HIQA) guidelines for the Economic Evaluation of Health Technologies in Ireland 2019.

Findings

Preliminary analysis is based on two practices that have completed intervention delivery. Following the audit, 19 patients were eligible to receive the intervention in Practice A and 30 patients in Practice B. The total cost of participation was €632 and €598 for practices A and B respectively. Intervention delivery (human resources) comprised 73% and 75% respectively of total cost, with delivery of reminders and information leaflets to eligible patients comprising 50% and 75% respectively of this cost. Variation in cost between practices was largely due to the number and profession of staff involved in intervention delivery.

Consequences

Economic costs should be captured and analysed routinely from the early stages of intervention development and piloting to inform efficient resource allocation for ongoing programme development and public health policy investment decisions. These costs will be used to inform economic analysis of a definitive trial of this intervention.