eprintid: 10173813 rev_number: 6 eprint_status: archive userid: 699 dir: disk0/10/17/38/13 datestamp: 2023-07-25 13:59:53 lastmod: 2023-07-25 13:59:53 status_changed: 2023-07-25 13:59:53 type: article metadata_visibility: show sword_depositor: 699 creators_name: Whiting, Daniel creators_name: Mallett, Sue creators_name: Lennox, Belinda creators_name: Fazel, Seena title: Assessing violence risk in first-episode psychosis: external validation, updating and net benefit of a prediction tool (OxMIV) ispublished: pub divisions: UCL divisions: B02 divisions: C10 divisions: D17 divisions: FI6 note: © Author(s) (or their employer[s]) 2023. This is an open access article distributed in accordance with the Creative Commons Attribution 4.0 Unported (CC BY 4.0) license (https://creativecommons.org/licenses/by/4.0/). abstract: BACKGROUND: Violence perpetration is a key outcome to prevent for an important subgroup of individuals presenting to mental health services, including early intervention in psychosis (EIP) services. Needs and risks are typically assessed without structured methods, which could facilitate consistency and accuracy. Prediction tools, such as OxMIV (Oxford Mental Illness and Violence tool), could provide a structured risk stratification approach, but require external validation in clinical settings. OBJECTIVES: We aimed to validate and update OxMIV in first-episode psychosis and consider its benefit as a complement to clinical assessment. METHODS: A retrospective cohort of individuals assessed in two UK EIP services was included. Electronic health records were used to extract predictors and risk judgements made by assessing clinicians. Outcome data involved police and healthcare records for violence perpetration in the 12 months post-assessment. FINDINGS: Of 1145 individuals presenting to EIP services, 131 (11%) perpetrated violence during the 12 month follow-up. OxMIV showed good discrimination (area under the curve 0.75, 95% CI 0.71 to 0.80). Calibration-in-the-large was also good after updating the model constant. Using a 10% cut-off, sensitivity was 71% (95% CI 63% to 80%), specificity 66% (63% to 69%), positive predictive value 22% (19% to 24%) and negative predictive value 95% (93% to 96%). In contrast, clinical judgement sensitivity was 40% and specificity 89%. Decision curve analysis showed net benefit of OxMIV over comparison approaches. CONCLUSIONS: OxMIV performed well in this real-world validation, with improved sensitivity compared with unstructured assessments. CLINICAL IMPLICATIONS: Structured tools to assess violence risk, such as OxMIV, have potential in first-episode psychosis to support a stratified approach to allocating non-harmful interventions to individuals who may benefit from the largest absolute risk reduction. date: 2023-06 date_type: published publisher: BMJ official_url: http://dx.doi.org/10.1136/bmjment-2022-300634 oa_status: green full_text_type: pub language: eng primo: open primo_central: open_green verified: verified_manual elements_id: 2031104 doi: 10.1136/bmjment-2022-300634 medium: Print pii: bmjment-2022-300634 lyricists_name: Mallett, Susan lyricists_id: SMALL45 actors_name: Flynn, Bernadette actors_id: BFFLY94 actors_role: owner funding_acknowledgements: 202836/Z/16/Z [Wellcome Trust]; BRC-1215-20005 [NIHR Oxford Health Biomedical Research Centre]; N/a [UCL/UCLH Biomedical Research Centre]; DRF-2018-11-ST2-069 [National Institute for Health Research (NIHR)] full_text_status: public publication: BMJ Ment Health volume: 26 number: 1 article_number: e300634 event_location: England citation: Whiting, Daniel; Mallett, Sue; Lennox, Belinda; Fazel, Seena; (2023) Assessing violence risk in first-episode psychosis: external validation, updating and net benefit of a prediction tool (OxMIV). BMJ Ment Health , 26 (1) , Article e300634. 10.1136/bmjment-2022-300634 <https://doi.org/10.1136/bmjment-2022-300634>. Green open access document_url: https://discovery.ucl.ac.uk/id/eprint/10173813/1/e300634.full.pdf