mHealth Service Linkage for Young Adults Impacted by the Criminal Legal System

Substance use service linkage will be attendance at a substance use service appointment via self-report via the question: " Did you attend your first appointment with your substance use treatment provider?" Yes or No. We will report the number of participants that answered with each response option.

Pre-exposure Prophylaxis linkage will be self-reported engagement in PrEP related services in the last month via the question " Have you received any PrEP-related services in the past [month/3 months]?" Yes or No. We will report the number of participants that answered with each response option.

PrEP referral be reported via self-report via the question: "Has your navigator offered to connect you to PrEP services?" Yes or No. We will report the number of participants that answered with each response option.

Time to linkage will be reported by the LYNX navigator based on the date they referred the participant to PrEP services and the date they recorded the participant first attended a PrEP related appointment. We will report the average number of days between the date of referral and first appointment attendance.

Receipt of a PrEP prescription will be identified via self-report via the question "Have you received a prescription for PrEP?". Yes or No. We will report the number of participants that answered with each response option.

Fill of a PrEP prescription will be identified via self-report via the question: "Have you filled your PrEP prescription?" Yes or No. We will report the number of participants that answered with each response option.

PrEP initiation will be identified via self-report via the question: "Have you started to take PrEP?" Yes or No . We will report the number of participants that answered with each response option.

PrEP adherence will be identified via self-report via the question: "In the past 30 days, rate your ability to take your PrEP medications as prescribed?" Very often, Somewhat often, Often, Not very often, Never. We will report the number of participants that answered with each response option.

PrEP persistence will be identified through self-report via the question: "Have you stopped taking PrEP?: Yes or No. We will report the number of participants that answered with each response option.

Accepted substance use treatment referral will be reported via self-report via the question: "Has your navigator offered to connect you to substance use services?" Yes or No. We will report the number of participants that answered with each response option.

Time to linkage will be reported by the LYNX navigator based on the date they referred the participant to substance use services and the date they recorded the participant first attended a substance use related appointment. We will report the average number of days between the date of referral and first appointment attendance.

The Navigation Satisfaction Tool (NAVSAT) includes twelve items that address client satisfaction with navigation services (e.g., How satisfied are you with the navigator's ability to listen and understand your concerns? How satisfied are you with the frequency of contact with the navigator?). Items are rated on a Likert scale from 1 (extremely dissatisfied / extremely unhelpful) to 7 (satisfied/ extremely satisfied). A total item score is calculated. Higher scores reflect greater navigator satisfaction. We will report the mean and the standard deviation for the NAVSAT score.

The Study Participant Feedback Questionnaire (SPFQ) comprises 23-questions and is split into three brief, validated questionnaires capturing trial experience at baseline, mid-point, and end of the study. The majority of items use a 5-point Likert satisfaction response scale. Some questions use a yes/no scale. The SPFQ is not designed to produce a single composite score. Responses will be analyzed item by item and reported as frequency distributions for each individual question, by response.

The Perceived Navigator Similarity scale consists of 10 items - 5 related to personal similarity and 5 related to ethnic similarity. Patients respond to each item using a 6-point Likert scale ranging from 0 (very different) to 5 (very similar). We will calculate a total score by summing all items, with higher scores indicating greater perceived similarity.