Acceptability and feasibility of using contingency management for cannabis reduction in specialist mental health services for psychosis: A qualitative study of staff views

AIM: There is increasing evidence linking cannabis use to onset, continuation, and relapse of psychosis. Contingency Management (CM) is discussed as a candidate intervention to reduce cannabis use. Our study aimed to explore staff views on the feasibility and acceptability of using CM for cannabis reduction in early intervention services for psychosis (EIS), in order to inform wider learning about implementation of such approaches in mental health services. SETTING: EIS teams in England. METHOD: Semi-structured interviews and focus groups analysed thematically. PARTICIPANTS: Forty managers and staff members working in mental health services where a CM intervention was delivered as part of a trial, four staff who delivered CM in these settings, and three key informants (academic experts in relevant fields). INTERVENTION: A complex intervention comprising CM with incremental financial incentives (vouchers) for reducing or stopping cannabis use, and psychoeducation about the risks of cannabis use. FINDINGS: Acceptability appeared to depend on how well the intervention was seen to fit with the service setting and ethos. Concerns included who should deliver CM; potential impacts on the therapeutic relationship; the ethics of using incentives to reduce socially objectionable behaviours; and how CM fits with the work of mental health practitioners. Feasibility concerns centred on resource limitations including time, cost, training, and national guidance and commissioning. CONCLUSIONS: Staff attitudes are likely to be a crucial influence on successful implementation of contingency management for cannabis reduction in specialist mental health settings. Several contextual barriers would need to be overcome to increase the acceptability of the intervention for use in early intervention services for psychosis.