Level of Care Utilization System for Psychiatric and Addiction Services

Since the arrival of managed care programs and principles, the use of quantifiable measures to guide assessment, level of care placement decisions, continued stay criteria, and clinical outcomes has been increasingly important. Until the development of LOCUS by the American Association of Community Psychiatrists (AACP) in 1996, there had been no widely accepted standards to meet those needs. Healthcare reforms in recent years have emphasized implementation of objective and uniform measurements for decision-making throughout the health care system. LOCUS is now used extensively in 26 states and in several international locations, and provides a single instrument that can be used for these functions in diverse settings and systems.

Integrating behavioral health and physical health concerns, it provides a common language and set of standards with which to make consistently sound judgments and recommendations. With LOCUS, clinicians and managers of healthcare resources have an instrument that is simple, easy to understand and use, but is also meaningful and sufficiently sensitive to distinguish appropriate needs and services. It provides clear, reliable and consistent measures that are relevant for making decisions related to quality of care, quality improvement and resource allocation.

Both LOCUS and CALOCUS have four main objectives. The first is to provide a system for assessment of service needs based on six evaluation parameters. The second is to describe a continuum of service intensities, characterized by the amount and scope of resources available at each "level" of care, in each of four categories of service. The third is to create a methodology for quantifying the assessment of service needs to permit reliable determinations for placement in the service continuum. The fourth is to facilitate clinical management and documentation.

This system is a dynamic one, and it has evolved over the years of its development. Its simple style and structure has invited use not only by a variety of clinicians with various levels of training, but also by service users themselves. This allows assessment to become a collaborative process. Engagement in this collaboration is central to person centered treatment planning. We continue to encourage collaboration in the assessment process whenever this is possible, and the accessible language of the instruments accommodates that process.

The LOCUS and CALOCUS instruments continue to demonstrate multiple potential uses:

At the individual client level:

  • To assess immediate service needs (e.g., for clients in crisis)

  • To monitor the course of recovery and service needs over time

  • To provide valid, value driven guidance to payers for medical necessity criteria the application of which will better meet the needs of clients in real world systems

  • To inform treatment planning processes

At the system or population level:

  • To plan system level resource needs for complex populations over time and help identify deficits in the service array

  • To assist in the development of bundled payments or case rates for episodes of care for specific clinical conditions

  • To provide a framework for a comprehensive system of clinical management and documentation

  • To facilitate communication between systems of care regarding service intensity needs

While LOCUS and CALOCUS are simple and straightforward to use, we highly recommend anyone performing LOCUS or CALOCUS assessments be trained by a certified LOCUS trainer.

LOCUS and CALOCUS were developed by members of the American Association for Community Psychiatry (AACP) and transformed into electronic versions by Deerfield Solutions.

Find out more about Training on LOCUS / CALOCUS

"Beyond assisting in service intensity placement decisions, these instruments (LOCUS and CALOCUS) can be used by systems to identify service gaps and to aid in projecting resource needs. The instruments provide guidance in treatment and recovery planning and help to ensure the best value for intended outcomes. They are useful for communication with managed care entities and to meet requirements for "least restrictive service alternatives" for Olmstead compliance. “

- Wesley E. Sowers, M.D., Director, Center for Public Service Psychiatry, Western Psychiatric Institute and Clinic

LOCUS RESOURCES & SOFTWARE (access to LOCUS/CALOCUS software and training)

Demo Version: LOCUS 20 (an abridged pdf of the most recent version of the LOCUS)

Demo Version: CALOCUS 20 (an abridged pdf of the most recent version of the CALOCUS)

LOCUS and CALOCUS Service Manager Software

For more information, visit LOCUS Solutions


The American Academy of Child and Adolescent Psychiatry (AACAP) and the American Association for Community Psychiatry (AACP) have recently unified the Child and Adolescent Level of Care Utilization System (CALOCUS) and the Child and Adolescent Service Intensity Instrument (CASII) into a single instrument, the Child and Adolescent Level of Care/Service Intensity Utilization System (CALOCUS-CASII) for ages 6-18. Moving forward, AACP and AACAP will continue development, improvement, and joint distribution of CALOCUS-CASII and its associated training materials, with the goal of delineating and continually improving the evidence-based standard for assessment of service intensity needs by providers and payers.

Current users of the CALOCUS, including the Deerfield online platforms and scoring algorithms, may continue to use those materials

To receive ongoing updates and current information about this merged tool please visit