Trial Outcomes & Findings for An App to Reduce Cannabis Use Among Emerging Adults (NCT NCT05824754)

NCT ID: NCT05824754

Last Updated: 2025-06-12

Results Overview

% of participants who consented to the study who download the MiWaves app.

• Recruitment status: COMPLETED
• Study phase: NA
• Target enrollment: 122 participants
• Primary outcome timeframe: 1 month
• Results posted on: 2025-06-12

Participant Flow

Participant milestones

Measure	JITAI Experimental: Within-participant micro-randomization Twice daily in the study, a participant is assigned to receive a message or no message. The micro-randomization will be performed by a reinforcement learning algorithm based on the participant's engagement with the intervention. Just-In-Time-Adaptive-Intervention (JITAI): Behavioral: MiWaves behavioral messages Participants will be using the MiWaves mobile app for 30 days. When a participant is assigned to receive a message, a message will be randomly selected from a pool of intervention message sets. Messages are based in motivational interviewing and include affect management and behavioral economic strategies.
Overall Study STARTED	122
Overall Study COMPLETED	122
Overall Study NOT COMPLETED	0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

An App to Reduce Cannabis Use Among Emerging Adults

Baseline characteristics by cohort

Measure	JITAI n=122 Participants Experimental: Within-participant micro-randomization Twice daily in the study, a participant is assigned to receive a message or no message. The micro-randomization will be performed by a reinforcement learning algorithm based on the participant's engagement with the intervention. Just-In-Time-Adaptive-Intervention (JITAI): Behavioral: MiWaves behavioral messages Participants will be using the MiWaves mobile app for 30 days. When a participant is assigned to receive a message, a message will be randomly selected from a pool of intervention message sets. Messages are based in motivational interviewing and include affect management and behavioral economic strategies.
Age, Categorical <=18 years	7 Participants n=5 Participants
Age, Categorical Between 18 and 65 years	115 Participants n=5 Participants
Age, Categorical >=65 years	0 Participants n=5 Participants
Age, Continuous	21.7 years STANDARD_DEVIATION 2.0 • n=5 Participants
Sex: Female, Male Female	65 Participants n=5 Participants
Sex: Female, Male Male	57 Participants n=5 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	19 Participants n=5 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	103 Participants n=5 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	0 Participants n=5 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants n=5 Participants
Race (NIH/OMB) Asian	6 Participants n=5 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=5 Participants
Race (NIH/OMB) Black or African American	12 Participants n=5 Participants
Race (NIH/OMB) White	89 Participants n=5 Participants
Race (NIH/OMB) More than one race	14 Participants n=5 Participants
Race (NIH/OMB) Unknown or Not Reported	1 Participants n=5 Participants
Region of Enrollment United States	122 participants n=5 Participants

PRIMARY outcome

Timeframe: 1 month

Population: App feasibility outcome is operationalized as % of participants who consented to the study who download the MiWaves app. Not all that consented to the study were included in study flow since not all that consented downloaded the app. Therefore, the number analyzed for app feasibility is greater than the number in the participant flow.

% of participants who consented to the study who download the MiWaves app.

Outcome measures

Measure

JITAI n=137 Participants Experimental: Within-participant micro-randomization Twice daily in the study, a participant is assigned to receive a message or no message. The micro-randomization will be performed by a reinforcement learning algorithm based on the participant's engagement with the intervention. Just-In-Time-Adaptive-Intervention (JITAI): Behavioral: MiWaves behavioral messages Participants will be using the MiWaves mobile app for 30 days. When a participant is assigned to receive a message, a message will be randomly selected from a pool of intervention message sets. Messages are based in motivational interviewing and include affect management and behavioral economic strategies.

App Feasibility

122 Participants

PRIMARY outcome

Timeframe: 1 month

Participants will complete acceptability ratings for the MiWaves app within their post-test assessment (percent with positive rating).

Outcome measures

Measure

JITAI n=112 Participants Experimental: Within-participant micro-randomization Twice daily in the study, a participant is assigned to receive a message or no message. The micro-randomization will be performed by a reinforcement learning algorithm based on the participant's engagement with the intervention. Just-In-Time-Adaptive-Intervention (JITAI): Behavioral: MiWaves behavioral messages Participants will be using the MiWaves mobile app for 30 days. When a participant is assigned to receive a message, a message will be randomly selected from a pool of intervention message sets. Messages are based in motivational interviewing and include affect management and behavioral economic strategies.

App Acceptability

90 Participants

Adverse Events

JITAI

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Inbal Billie Nahum-Shani

University of Michigan

Phone: 7346609626

Email: inbal@umich.edu

Results disclosure agreements

• Principal investigator is a sponsor employee
• Publication restrictions are in place