Evaluation of a model of violence risk assessment (HCR-20) among adult patients discharged from a gazetted psychiatric hospital in Hong Kong

Abstract

Background: Structured professional judgement (SPJ) method has been considered as a useful approach to violent risk assessment. However, an unstructured clinical model of violence risk assessment, the Priority Follow-up (PFU) system is employed in Hong Kong. The Historical/Clinical/Risk Management – 20 (HCR-20) is the SPJ instrument that had been most researched but has not been previously validated in a Chinese population. Study design and methods: HCR-20 was completed for 110 discharged general adult or forensic psychiatric patients with a PFU status and also for the same number of demographically matched controls. Violence was determined from case notes at 6- and 12-month after the HCR-20 rating. Results: HCR-20 was rated with acceptable interrater reliability. The predictive validity of the structured final risk judgement was significant, yielding moderate to large effect sizes, for all of the violent outcomes at 6 and 12 months. When compared with the PFU system, the final risk judgement yields no significant differences.

Keywords:

• HCR-20
• violence risk assessment
• PFU system

Acknowledgements

I would like to thank the Food and Health Bureau of Hong Kong for sponsoring this project as one of the selected researches for Commissioned Research on Mental Health Policy and Services. I would also like to thank the Department of Forensic Psychiatry and Castle Peak Hospital for their support as well as our research assistants, Ms Sze Lok Ma and Mr. Harry Ho for their hard work.