For patients randomized to the CC arm, in addition to the provider being alerted to the positive Mental Health and Substance Use Disorder screener, the patient will also be assigned to a peer case manager (P-CM). The P-CM will provide longitudinal care for the patient as part of their care management case load. The collaborative care support team will include the P-CM, a consultant addiction psychiatrist and the patient's HIV provider who will implement a stepped care program consisting of: 1) an initial assessment, determination of and implementation of an individualized care plan to provide; 2) psychosocial and medication adherence support; 3) evidence-based brief intervention incorporating motivational interviewing informed strategies; 4) measurement-based care for Mental Health and Substance Use Disorder provided directly by the HIV primary care provider or in collaboration with specialty Mental Health and Substance Use Disorder services.

For patients randomized to the UC referral arm, the patient's HIV provider will receive an electronic alert of the patient's positive screen for a Mental Health and Substance Use Disorder. The patient will not be contacted by the P-CM. The provider, at their discretion, will initiate referral to the psychiatry service available onsite. For patients with Substance Use Disorder, providers refer to the in-clinic Substance Use Disorder treatment program that is managed by a nurse practitioner with Substance Use Disorder care experience. Once referred, the patient is seen by the nurse practitioner (separate from the HIV provider) who manages prescription of and assessment of adherence to buprenorphine, including monitoring of urine toxicology results with support from an addiction counselor. The Bartlett Clinic runs 2 substance use groups weekly and has processes for referral to a higher level of Substance Use Disorder care at offsite Substance Use Disorder treatment programs.

Collaborative care (CC) is an evidence-based model of integrated mental health and substance use disorder care endorsed by the American Psychiatric Association for the integration of mental health and substance use disorder care into primary care settings. CC includes the following components: 1) A collaborative care team of multidisciplinary health care providers consisting of the primary physician, a care manager and a consulting psychiatrist, providing care in a coordinated fashion; 2) A population focus with the team working together to provide care and continuously measure and track health outcomes of a defined population of patients; 3) A measurement-guided approach with systematic use of disease specific patient reported outcome measures, such as symptom rating scales like the PHQ-9 to drive clinical decision making; and 4) Evidence-based practices with the team adapting scientifically proven treatments within an individual clinical context to achieve improved health outcomes.

This is defined as a viral load < 200 copies/ml

At least 2 medical visit dates, specifically for HIV care, that are at least 90 days apart