GAMBLINGLESS: IN-THE-MOMENT: A micro-randomised trial of a gambling Just-In-Time Adaptive Intervention

GAMBLINGLESS: IN-THE-MOMENT is a Just-In-Time Adaptive Intervention (JITAI) delivered via a smartphone app for people who want to gamble less. The aim of this cognitive-behavioural therapeutic intervention is to prevent cravings, low self-efficacy in high-risk situations, and positive outcome expectancies from transitioning into gambling episodes. GAMBLINGLESS: IN-THE-MOMENT is informed by the reformulated relapse prevention model. This JITAI employs decision rules specifying that participants who are in a state of receptivity (available for treatment) and report a state of cognitive vulnerability characterised by high craving intensity, low self-efficacy, or positive outcome expectancies (tailoring variables) in Ecological Momentary Assessments (EMAs) sent during three semi-random times a day (decision points) are delivered tailored cognitive-behavioural activities targeting these cognitive processes (intervention options). These components are guided primarily by the long-term goal of reducing gambling symptom severity (distal outcome), which is posited to be achieved through the short-term goal of reducing the likelihood of gambling episodes (primary proximal outcome) via reduced craving intensity, enhanced self-efficacy, and lowered positive outcome expectancies (secondary proximal outcomes). Trial design A micro-­randomised trial (MRT), a form of sequential factorial design, will be employed to inform the optimisation of this JITAI. In this MRT, each participant will be randomised to a tailored intervention condition or a no intervention control condition at each decision point across a 28-day period. The MRT will be supplemented with: (1) a within-group follow-up evaluation to explore the longer-term outcomes of the intervention in relation to the primary (gambling symptom severity) and secondary (gambling frequency, gambling expenditure, cravings, self-efficacy, and positive outcome expectancies) outcomes from the pre-intervention evaluation to the post-intervention and six-month follow-up evaluations; and (2) an evaluation of the usability and acceptability of the JITAI using items in the post-intervention evaluation, indices of app usage and engagement, and qualitative telephone interviews. EMA features: All participants will be prompted to complete time-based EMAs (t-EMAs) via push notifications at random times during three pre-specified periods (morning, afternoon, and evening). These in-app t-EMAs will consist of single items assessing craving intensity, self-efficacy, positive outcome expectancies (tailoring variables), as well as psychological distress, impulsivity, subjective alcohol intoxication, readiness to change, gambling availability (financial), gambling availability (location), and social context. These items are mostly measured on 5-point Likert scales (from 0-4). The t-EMAs will also include a gambling event record, which will assess gambling episodes (and gambling expenditure) since the last t-EMA completed (e-EMA) (see Primary Outcome). Intervention content: This app intervention comprises 53 activities in total (1-15 minutes each to complete), spanning three tailored interventions (modules) detailed below. Selected activities were developed for smartphone delivery with a focus on engagement, interactivity, user preferences, participant literacy, inclusiveness, and ease of use, with an aim to encourage autonomy and create an aesthetically pleasing design. Activities were interactive and gamified using multimedia delivery strategies, comprising a combination of video activities, audio activities, personalised feedback, quizzes, open-ended items, and multiple-choice items. Intervention 1 Curbing Craving - This intervention comprises 10 activities to help participants manage their gambling cravings to prevent them from transitioning into a gambling episode. Intervention 2 Tackling Triggers - This intervention contains 25 activities evenly spanned across five types of high-risk situations/triggers, including: (1) financial pressures; (2) unpleasant emotions; (3) social pressure to gamble; (4) testing control over gambling; and (5) conflict with others. Activities aim to improve self-efficacy to resist an urge to gamble in these specific types of high-risk situation. Intervention 3 Exploring Expectancies - This intervention contains 18 activities evenly spanned across three types of positive outcome expectancies, including: (1) excitement; (2) escape; and (3) money. Activities aim to redress that specific type of positive outcome expectancy. Intervention options: Responses to t-EMA items assessing craving intensity, self-efficacy, and positive outcome expectancies (tailoring variables) will be used to determine eligibility for the delivery of the tailored intervention according to a set of predetermined decision rules (>0 on each tailoring variable). Participants who do not exceed the cut-point for any of the relevant t-EMA items will not be eligible for any intervention. These participants will receive a short encouraging message and their interaction with the app will end. Importantly, participants who exceed the cut-point for intervention delivery at each t-EMA will be micro-randomised to one of two conditions: (1) a no intervention control condition (in which the participant will receive an encouraging message and their interaction with the app will end) or (2) tailored intervention condition. The micro-randomisation procedure will involve a 25% chance of receiving the intervention control condition and a 75% chance of receiving a tailored intervention condition. Participants who are eligible for more than one intervention will be randomly allocated to an intervention (37.5% chance of receiving either intervention when eligible for two interventions; and 25% chance of receiving any of the intervention when eligible for three interventions). In the tailored intervention condition, if participants are randomised to receive the Curbing Cravings intervention, they will have the option of selecting which of the 10 activities they want to complete. If participants are randomised to receive the Tackling Triggers or Exploring Expectancies interventions, participants first have to select which of the five high-risk situations or three positive outcome expectancies, respectively, they would like to address in that moment, and then select an activity from that specific group. Following completion of an intervention activity, participants will be required to complete a post-intervention EMA item specific to the activity completed. Their response to this post-intervention EMA item will be subjected to the same eligibility criteria threshold employed for the t-EMAs. Participants who do not reach exceed the cut-point on the post-intervention EMA item will be presented with an encouraging message and their interaction with the app will end until the next t-EMA. Participants who exceed the cut-point on the post-intervention EMA item are returned to the relevant intervention activity group and asked to select another activity, creating an intervention loop that continues until the participant no longer exceeds the cut-point or closes the app. Importantly, GAMBLINGLESS: IN-THE-MOMENT includes a “provide nothing” option in situations in which the participant is unreceptive, support is not required, or the provision of support may be unsafe, inconvenient or unethical. Specifically, support will not be offered if the push notification prompting EMA completion is ignored or they press the “snooze” function indicating that are currently unable to complete the EMA (i.e., they are not receptive). Individuals will be allowed two hours to complete an EMA to preserve the momentary nature of the intervention while accommodating the potential for possible unavailability (e.g., driving, working) of the participant at the initial notification time. Notably, the micro-randomised trial will be conducted over a 28-day period. During this time, intervention activities will only be available in response to the push notification (“push” intervention). These notifications will not be delivered during a six-month follow-up period, but the intervention content will be available to participants “on-demand” during this time (tailored “pull” intervention). During this period of time, participants will be able to access the same tailored intervention activities via a participant-initiated t-EMA.