To adapt the Assertive Community Treatment (ACT) Model for use for use among hard-to-treat people with severe mental illness (SMI) in a medium-size mental health service area in The Netherlands.

Our adaptation does not include individual research assessments of clients in order to minimize their burden and maximize their participation in the services. It consists of three inter-related phases. Phase One includes: a) identification of 30 of the most difficult patients to treat for this trial, among long-term care clients (N: 820) of Renier van Arkel Psychiatric Services in s-Hertogenbosch; b) Collection of one-year Case Register data on participant's service use and clinical and demographic variables prior to this trial. Phase Two includes: a) Provision of in-vivo training to a team to work with the ACT methodology; b) Assessing over a year the provision of ACT, including follow-up service use and data collection from charts on substance use, quality of life and case-management. In Phase Three, we adapt ACT for use in our area and produce an intervention manual based on our experience in this trial, collected data, and on our overall clinical and research experience with hard-to-engage populations.

We successfully identified our target group, initiated the team in-vivo training and the ACT service provision. The rest of the study is still being implemented.

Initial assessments suggest that adapting an evidence-based intervention based on collection of clinical implementation data and non-intrusive collection of available service use and clinical variables data might be a useful method.