Text Messaging Intervention for Postpartum Alcohol Use: Micro-Randomized Trial Supports Feasibility, Acceptability,...

This pilot micro-randomized trial (MRT) evaluated the feasibility of the MRT design and compared the acceptability and preliminary impacts of drinking-focused and maternal-focused text messages to inform the development of a tailored, just-in-time adaptive text messaging intervention for postpartum at-risk alcohol use.

Postpartum mothers (N = 65) participated in a 28-day MRT. Participants completed ecological momentary assessment (EMA) surveys upon waking (morning survey) at two random times daily (hourly surveys), with an optional night survey (night survey). After each hourly and night survey, participants were randomized to receive either a maternal-focused message, a drinking-focused message, or no message. Check-in surveys assessed intermediate (motivation, maternal self-efficacy, drinking self-efficacy, self-regulation, and craving) and primary (alcohol use) outcomes 15 minutes later.

Compliance rates for all survey types exceeded 70%, except for optional night surveys. Participants reported a low burden associated with the MRT. Participants were more likely to rate maternal-focused messages as helpful and evoking positive feelings compared with drinking-focused messages. A significant effect of receiving an intervention message (vs. no message) was found for drinking self-efficacy (DSE), with those who received a message reporting higher DSE than those who received no message, and no difference between message types. Significant time-by-condition interactions revealed that the effect of maternal messages decreased over time, whereas DSE increased over time for the control condition.

Findings support the feasibility and acceptability of the MRT design in postpartum mothers with at-risk drinking histories and inform the development of a tailored text messaging intervention for this population.