MedicalResearch.com Interview with:
Zheng Chang, PhD
Department of Medical Epidemiology and Biostatistics
Medical Research: What is the background for this study? What are the main findings?
Dr. Chang: More than 30 million people are released from prison worldwide every year. Despite reported decreases in violence in many countries, repeat offending remains high across many high-income and middle-income countries. Because there is considerable inconsistency and inefficiency in identifying those who are at high risk of reoffending and most in need of interventions, we developed and validated a clinical prediction rule to determine this risk in released prisoners.
We did a cohort study of 47 326 prisoners released in Sweden between 2001 and 2009. We developed a 14-item model to predict violent reoffending, which includes modifiable risk factors and has been externally validated. The model showed good measures of discrimination and calibration. The study uses the methods to develop the prediction model on the basis of TRIPOD guidelines, and it is a brief, easy to use, and scalable tool. This tool has also been translated into a freely available web application (OxRec).
Medical Research: What should clinicians and patients take away from your report?
Dr. Chang: Criminal justice and community health services can potentially improve reoffending outcomes, particularly if they work together on modifiable risk factors (e.g., psychiatric and substance use disorders). This risk score can assist in identifying prisoners on release who are at high risk of violent reoffending, and might benefit from interventions to counteract the cycle of reoffending and improve their quality of life.
Medical Research: What recommendations do you have for future research as a result of this study?
Dr. Chang: Future research could compare the performance of OxRec against currently used instruments in the same sample. Further assessments in countries with different prison populations are also needed.
Prediction of violent reoffending on release from prison: derivation and external validation of a scalable tool
Fazel, Seena et al. Published Online: 13 April 2016
The Lancet Psychiatry , Volume 0 , Issue 0 , DOI: http://dx.doi.org/10.1016/S2215-0366(16)00103-6