The EUROHIS-QOL (European Health Interview Survey-Quality of Life) 8-item index is an efficient, valid, and reliable measure of four quality of life domains (physical, psychological, environmental, and social). Items are rated on a 5-point Likert-type scale and summed to produce a total quality of life score (Range: 8-40) with higher scores indicating a higher level of satisfaction with their current quality of life. Change in scores from baseline to 4-week follow-up was examined with a higher change score indicating a greater increase in participant quality of life.

OCS is a 3-item measure of opioid craving with acceptable internal consistency, reliability, and concurrent/predictive validity. Participants rate their level of craving in reference to three situations (current, past week, and high-risk environment) on a scale ranging from 0-10 to produce a total score ranging from 0-30 with higher scores indicating greater reduction in craving. Change in OCS scores from baseline to 4-week follow-up was examined to determine reductions in craving.

Readiness Ruler is a valid and reliable 2-item measure of motivation and readiness to change. Participants rate their perceived "Importance" of making a change to their drug use behaviors, and their perceived "Confidence" in their ability to successfully achieve their goal (range: 0-100) with higher scores indicating greater motivation. Perceived "Importance" and "Confidence" scores are averaged to indicate a total Motivation score at 4-week follow-up (Range: 0-100).

BSCQ is an 8-item measure of self-efficacy for resisting the urge to use drugs in 8 high-risk situations based on the relapse prevention model (unpleasant emotions, physical discomfort, pleasant emotions, testing control, urges/temptations, interpersonal conflict, social pressure, and pleasant times with others). Patients rate their confidence in resisting the urge to use drugs in each of the 8 situations on a scale ranging from 0 (Not at all Confident) to 100 (Extremely Confident). Scores for each of the 8 situations are averaged to produce a total self-efficacy score (Range: 0-100). Change in scores from baseline to 4-week follow-up was examined with higher scores indicating a greater increase in self-efficacy.

Participant self-report will be used to determine frequency counts of the 11 opioid use disorder diagnostic criteria per Diagnostic & Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) with higher counts indicating a greater number of symptoms/opioid-related impairment present and higher opioid use disorder severity. Total score indicating the total number of positive diagnostic criteria ranges from 0-11. Change in the number of diagnostic criteria endorsed from baseline to 4-week follow-up was examined to determine reduction in opioid-related impairment with higher scores indicating a greater reduction in symptoms over time.

Assessed by % of participants fully-adherent to weekly outpatient individual therapy visits, community-based mutual-help recovery support meetings, and other scheduled appointments attended during study period with higher values indicating greater care plan adherence.

Assessed by % of participants completing assessment surveys during study period with higher values indicating greater survey participation.

Assessed by participant self-report and positive urine drug screens completed at routine clinic visits during study period.

Assessed by participant self-report and positive urine drug screens completed at routine clinic visits during study period for non-opioids substances (alcohol, cannabis, methamphetamine, amphetamines, cocaine, benzodiazepines).

The EUROHIS-QOL (European Health Interview Survey-Quality of Life) 8-item index is an efficient, valid, and reliable measure of four quality of life domains (physical, psychological, environmental, and social). Items are rated on a 5-point Likert-type scale and summed to produce a total quality of life score (Range: 8-40) with higher scores indicating a higher level of satisfaction with their current quality of life. Change in scores from baseline to 4-week follow-up was examined with a higher change score indicating a greater increase in participant quality of life.

OCS is a 3-item measure of opioid craving with acceptable internal consistency, reliability, and concurrent/predictive validity. Participants rate their level of craving in reference to three situations (current, past week, and high-risk environment) on a scale ranging from 0-10 to produce a total score ranging from 0-30 with higher scores indicating greater reduction in craving. Change in OCS scores from baseline to 4-week follow-up was examined to determine reductions in craving.

Readiness Ruler is a valid and reliable 2-item measure of motivation and readiness to change. Participants rate their perceived "Importance" of making a change to their drug use behaviors, and their perceived "Confidence" in their ability to successfully achieve their goal (range: 0-100) with higher scores indicating greater motivation. Perceived "Importance" and "Confidence" scores are averaged to indicate a total Motivation score at 4-week follow-up (Range: 0-100).

BSCQ is an 8-item measure of self-efficacy for resisting the urge to use drugs in 8 high-risk situations based on the relapse prevention model (unpleasant emotions, physical discomfort, pleasant emotions, testing control, urges/temptations, interpersonal conflict, social pressure, and pleasant times with others). Patients rate their confidence in resisting the urge to use drugs in each of the 8 situations on a scale ranging from 0 (Not at all Confident) to 100 (Extremely Confident). Scores for each of the 8 situations are averaged to produce a total self-efficacy score (Range: 0-100). Change in scores from baseline to 4-week follow-up was examined with higher scores indicating a greater increase in self-efficacy.

Participant self-report will be used to determine frequency counts of the 11 opioid use disorder diagnostic criteria per Diagnostic & Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) with higher counts indicating a greater number of symptoms/opioid-related impairment present and higher opioid use disorder severity. Total score indicating the total number of positive diagnostic criteria ranges from 0-11. Change in the number of diagnostic criteria endorsed from baseline to 4-week follow-up was examined to determine reduction in opioid-related impairment with higher scores indicating a greater reduction in symptoms over time.

SUS is a 10-item measure commonly used for global assessments of systems usability. SUS scores will be used to objectively quantify the usability of the PROCare recovery app. Participants allocated to the PROCare condition will rate the usability of the app on 10 items assessing different aspects of usability using a Likert-type scale ranging from 1 (Strongly Disagree) to 5 (Strongly Agree) with higher converted total scores indicating a higher level of overall usability. Converted total scores range from 0-100 with SUS scores above 68 considered Above Average.

Only participants who used the PROCare Recovery app were administered the measure of app usability.

Treatment-as-Usual