Evaluating innovative treatments in forensic mental health: A role for single case methodology?

TLDR

Rapid expansion of forensic mental health services has created a demand for evidence, yet outcomes research for mentally disordered offenders remains sparse compared to non‑disordered populations. This paper argues that single‑case research methods can address this evidence gap. The authors review the strengths and limitations of single‑case designs relative to RCTs, especially in DSPD services, and outline key strategic decisions for their implementation.

Abstract

Abstract The rapid development of new forensic mental health services and treatments has created a demand for research and evidence relating to the effectiveness of interventions. Unfortunately, the literature on outcomes of treatments for mentally disordered offenders is sparse, compared with the substantial 'what works' literature regarding non-disordered offenders in the criminal justice system. In this paper we propose that single case research methodologies have a part to play in remedying this unsatisfactory state of affairs. The strengths and limitations of single case methods are discussed and comparisons made with RCTs, particularly in the context of dangerous and severe personality disorder (DSPD) services in England and Wales. Important strategic decisions that need to be made in relation to the implementation of single case experimental methods are outlined.