Assessing vulnerability to risk of suicide and self-harm in prisoners: a Rasch analysis of the suicide concerns for offenders in the prison environment (SCOPE-2)

BACKGROUND: With increasing levels of suicide and self-harm behaviour in the criminal justice system professionals would benefit from a tool that can identify individuals who may be at risk of self-harm and/or suicidal behaviour. METHOD: The Suicide Concerns for Offenders in the Prison Environment (SCOPE) tool was originally devised and validated in six UK prisons between 2003 and 2004. The goal of this study is to re-evaluate the SCOPE using Rasch methodology to produce a psychometrically robust instrument. Data were presented from 1051 SCOPE assessments of male and female offenders. RESULTS: The analysis produced a revised SCOPE-2 tool reducing the tool from a 27 to a 19 items and simplifying the categorical six point scale to a four item scale. CONCLUSIONS: Further validation of the new SCOPE-2 tool is required in samples of male and female prisoners to assess different cut-off points for clinical and policy use.