Mobile crisis effectiveness: a systematic review and associated functions and forms framework

Increased demand for mental health crisis services and falling supply of inpatient psychiatric beds in the United States (U.S.) has led to heavy investment in mobile crisis units (MCUs), teams of mental health professionals that de-escalate crises in the community and aim to prevent emergency department visits, arrests, self-harm, etc. Despite nearly two thousand such services being active in the U.S., the last review of MCUs, conducted in 1995, found no evidence of their effectiveness. It is not known if newer research validates the effectiveness of this widely used intervention, nor how aligned the goals and functions of the many MCUs are. This article systematically reviews the literature since 2000 to determine the effectiveness of MCUs in the U.S. and create a theoretical framework of their functions and forms to aid future research efforts.

A systematic review was conducted by using a keyword search in PubMed, PsycINFO, and Scopus. Articles were included through June 2025 and excluded if they were published before 2000 or were not from the U.S. Quality of included articles was assessed using the Mixed Method Appraisal Tool. The Functions and Forms Framework for describing complex healthcare interventions was used to identify the core elements of MCUs and design a theoretical framework for their functions.

Of the 134 studies included in title/abstract screening, nine met inclusion criteria and were found to be medium or high quality. One quasi-experimental study found evidence against MCU effectiveness, one randomized controlled trial found little evidence of MCU effectiveness, and four quasi-experimental studies, one pretest-posttest, one qualitative, and one retrospective cohort study found evidence supporting MCU effectiveness. Primary functions of MCUs included hospital diversion, justice-system diversion, and providing accessible patient-centered care in the community.

The limited evidence uncovered in this review offers tentative support for MCU effectiveness. However, the current literature is too sparse to draw firm or generalized conclusions. An initial theoretical framework was created to help practitioners and policymakers document the functions and forms of MCUs to increase the comparability of these services, and research recommendations were generated to fill gaps in the literature.