Gambling Habit Hacker: Protocol for a micro-randomised trial of planning interventions delivered via a Just-In-Time Adaptive Intervention for adult gamblers (Preprint)

Abstract

People with gambling problems frequently report repeated unsuccessful attempts to change behaviour. Even though a range of behaviour change techniques are available to individuals to reduce gambling harm, they can be challenging to implement or maintain in the moment. The provision of implementation support, tailored for immediate, real-time individualised circumstances, may improve attempts at behaviour change.

The aim of the current study is to develop and evaluate a Just-In-Time Adaptive Intervention (JITAI) for individuals who want support sticking to their gambling limits. The JITAI development is based on the principles of the Health Action Process Approach with delivery in alignment with the principles of Self-Determination Theory. The primary objective is to determine the effect of action and coping planning compared to no intervention on the goal of subsequently adhering to gambling expenditure limits.

Gambling Habit Hacker is delivered as a JITAI providing in-the-moment support for adhering to gambling expenditure limits (primary proximal outcome). Delivered via smartphone app, this JITAI delivers tailored Behaviour Change Techniques relating to goal setting, action planning, coping planning and self-monitoring. The Gambling Habit Hacker app will be evaluated with a 28-day micro-randomised trial (MRT). Up to 200 individuals seeking support for their own gambling from Australia and New Zealand will set a gambling expenditure limit (i.e., goal). They will then be asked to complete three Ecological Momentary Assessments (EMAs) per day over a 28-day period. EMAs will assess real-time adherence to gambling limits, strength of intention to adhere to goals, goal self-efficacy, urge self-efficacy and being in a high-risk situation. Based on responses to each EMA, participants will be randomised to the control (a set of 25 self-enactable strategies containing names only and no implementation information) or intervention (self-enactable strategy implementation information with facilitated action and coping planning) conditions. This MRT will be supplemented with: (i) a 6-month within-group follow-up which explores the longer-term impact of the app on gambling expenditure (primary distal outcome) and a range of secondary outcomes (gambling frequency, gambling symptom severity, psychological distress, well-being, situational confidence and planning propensity); (ii) an evaluation of acceptability of the JITAI via post-intervention surveys, app usage and engagement indices, and in-depth interviews.

The intervention has been subject to expert user testing, with high acceptability scores. The results will inform a more nuanced version of the Gambling Habit Hacker app for wider use.

Gambling Habit Hacker is part of a suite of interventions for addictive behaviours that deliver implementation support grounded in lived experience. This study may inform the usefulness of delivering implementation intentions in real-time and in real-world settings. It potentially offers people with gambling problems new support to set gambling intentions and stick to their limits.

This trial has been registered with the Australian New Zealand Clinical Trials Registry (ACTRN12622000497707) and has been approved by the Deakin University Human Research Ethics Committee (2020-304).