Standard care comprised a treatment network consisting of open and closed inpatient wards, day-clinics, an outpatient centre, and eight private psychiatrists. Each patient was treated by a private psychiatrist or by a psychiatrist in the outpatient centre. Home visits were possible, but office visits were the general rule. Patients were allowed to use all treatment offers in the outpatient centre. Outside office hours, patients could refer themselves to the psychiatric hospital. Psychosocial treatments as supportive therapy, psychoeducation, psychotherapy, and family intervention were provided infrequently and in a less intensive and unsystematic way, and only in the minority of cases. This 'standard of care' definition is in accordance with other studies.

ACT was structured and implemented according to guidelines of the Assertive Community Treatment Association (ACTA). Team members were highly educated psychosis experts consisting of a consultant psychiatrist, a psychiatrist, two psychologists, and a nurse, all of which received training in cognitive behavioral (CBT), dynamic, and/or family psychotherapy. Study participants could use all treatment options within the integrated care program such as psychoeducation groups, social skills training, family groups, motivational addiction therapy, meta-cognitive training etc.

The primary outcome of the study was the time to service disengagement (SD). This primary aim was chosen because the assertive approach of ACT is to prevent service disengagement3 and because service disengagement is a major predictor for relapse and thereby poor long-term outcome.16,17 Service disengagement was present, if a patient repeatedly refuses further treatment despite several attempts of reengagement (phone calls of patient and family in both treatment arms and potentially home visits in the ACT group).

Secondary outcomes comprised medication non-adherence, improvements of symptoms, functioning, quality of life, and satisfaction with care from patients and relatives perspectives.