Predicting self-harm in prisoners: Risk factors and a prognostic model in a cohort of 542 prison entrants

Abstract

Background. Self-harm is common in prisoners. There is an association between self-harm in prisoners and subsequent suicide, both within prison and on release. The aim of this study is to develop and evaluate a prediction model to identify male prisoners at high risk of self-harm. Methods. We developed an 11-item screening model, based on risk factors identified from the literature. This screen was administered to 542 prisoners within 7 days of arrival in two male prisons in England. Participants were followed up for 6 months to identify those who subsequently self-harmed in prison. Analysis was conducted using Cox proportional hazard regression. Discrimination and calibration were determined for the model. The model was subsequently optimized using multivariable analysis, weighting variables, and dropping poorly performing items. Results. Seventeen (3.1%) of the participants self-harmed during follow up (median 53 days). The strongest risk factors were previous self-harm in prison (adjusted hazard ratio [aHR] = 9.3 [95% CI: 3.3–16.6]) and current suicidal ideation (aHR = 7.6 [2.1–27.4]). As a continuous score, a one-point increase in the suicide screen was significantly associated with self-harm (HR = 1.4, 1.1–1.7). At the prespecified cut off score of 5, the screening model was associated with an area under the curve (AUC) of 0.66 (0.53–0.79), with poor calibration. The optimized model saw two items dropped from the original screening tool, weighting of risk factors based on a multivariable model, and an AUC of 0.84 (0.76–0.92). Conclusions. Further work is necessary to clarify the association between risk factors and self-harm in prison. Despite good face validity, current screening tools for self-harm need validation in new prison samples.

Risk factors for self-harm in prison: a systematic review and meta-analysis

“…Because prisoners are generally a population at high risk of selfharm, the identification of those at elevated risk of selfharm is a complex task, 16 and will probably require highquality methods and external validation. 82 Given that previous selfharm is among the strongest predictors of future selfharm [68][69][70] and suicide, 9,10 effective treatment interventions need development and assessing in prisoners who selfharm. Psychosocial interventions following selfharm, 83 including forms of cognitive behavioural therapy and group therapy, could be made available in prisons, although current evidence of effectiveness in custodial settings is weak.…”

Prevalence and risk factors for suicide attempts in prison

“…Mental health services need to be adequately resourced and linked to evidence-based interventions (Malik et al, 2021;Yoon et al, 2017) to address the high level of unmet need among people in prison (Jakobowitz et al, 2017). Targeted strategies aimed at high-risk groups will rely on early identification of risk (Ryland et al, 2020) and should be supplemented by organisational and establishment-wide interventions as part of a whole population approach. These include measures aiming to promote purposeful activity and meaningful social support, as well as those to reduce victimisation in prison (Favril, 2021;Marzano et al, 2016).…”

Epidemiology, Risk Factors, and Prevention of Suicidal Thoughts and Behaviour in Prisons: A Literature Review

“…To do so, suicide risk assessment should not be limited to a one-off event at the point of reception into prison, but must be an ongoing and systematic process at regular intervals throughout prisoners’ period of incarceration ( Marzano et al, 2016 ). Although screening tools are recommended by the WHO ( 2007 ) to guide risk stratification and inform treatment allocation, few such scales have yet been developed specifically for use in prison populations ( Gould et al, 2018 ) and further research is needed to test their reliability and predictive validity ( Horton et al, 2018 ; Ryland et al, 2020 ). Once risk has been identified, a multidisciplinary management process should be established with clearly articulated procedures and policies outlining responsibilities for placement, monitoring, and treatment ( Humber et al, 2011a ).…”