Fidelity of Intervention Delivery in the TRACE Programme Randomised Controlled Trial, a Complex Behavioural Intervention for Food Addiction

The 3-arm Targeted Research on Addictive and Compulsive Eating (TRACE) randomised controlled trial, aimed to decrease addictive eating symptoms in adults with the active intervention (dietitian-led telehealth sessions) compared to the passive intervention (self-guided workbook) and control group. The current study evaluated fidelity of the TRACE active intervention delivery to determine if telehealth sessions were delivered according to the intended service parameters: session durations (min), frequency and content. Differences between actual and intended schedules, for participants in the telehealth intervention arm (n = 39) were analysed. A subgroup of participants' (n = 5) sessions were audio recorded (n = 25 sessions) with n = 24 analysed to determine fidelity of session content against an observer implementation record. Fidelity of telehealth session duration and frequency was classified as 'good' and 'very good', respectively, with the median duration and days between each session within ±5 min or days, respectively. The dietitian's fidelity in delivering key components was rated as 'very good' by both independent reviewers (82% and 87.2%) respectively. The 'session summary' was the least covered topic, followed by 'determining the client's main food intake concerns'. The TRACE programme was delivered as intended based on the session duration and frequency, however observations made during the content analysis identified key content, including the 'session summary', was not always covered. Future trials should monitor fidelity in diverse settings and a range of professionals with variations in training and experience.Australian New Zealand Clinical Trials Registry (ACTRN12621001079831).