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We will recruit 400 participants at discharge (both planned or unplanned) from Illinois’ largest treatment organization and randomly assign them in a 2 x 2 factorial design to receive EMA only, EMI only, combined EMA+EMI, or neither (control). Participants in the 3 EMA and EMI groups will receive a smartphone and training after discharge.

To help them self-monitor, individuals in the EMA groups will be randomly signaled 6 times daily for 6 months and asked to record their recent substance use, HIV risk behaviors (e.g., needle use, unprotected sex) and exposure to internal and external protective and risk factors, then to rate the extent to which these factors support their recovery or make them want to use drugs or alcohol. Individuals in the EMI groups will have 24/7 access to A-CHESS. In the combined EMA+EMI group, participants will receive feedback directly following completion of each 2-3 minute EMA, and EMA responses will be used to encourage EMI utilization.

The AIMS of this experiment are to:

  • Aim 1. Test the effect of EMA, EMI and EMA+EMI on days of abstinence;
  • Aim 2. Test the effect of EMA, EMI and EMA+EMI on HIV risk behaviors; and
  • Aim 3. Evaluate the extent to which changes in days of abstinence mediate the effect of EMA, EMI, and EMA+EMI on HIV risk behaviors.

Partners / Participant Sites

  • Chestnut Health Systems, Lighthouse Institute, Chicago, IL
  • Haymarket Center, Chicago, IL

Funding Period:
May 1, 2014 - February 28, 2019
Principal Investigators:
David Gustafson Sr., Ph.D
Christy Scott, Ph.D.

Fiona McTavish