Completed PRISMA checklist.

<div><p>The structured professional judgement (SPJ) approach was initially developed to support risk assessment and management decisions. The approach is now being adapted and applied to admission assessments for adult secure services. This systematic review aims to summarise the evidence for the effectiveness and acceptability of the SPJ approach in admission assessments of this kind. A comprehensive electronic search strategy was used to identify studies indexed in PubMed, PsycInfo, Medline and Cochrane Library (January 2007 –January 2024). Two search strategies included terms (and synonyms) for psychiatric patients (quantitative) or clinicians and clinicians’ experiences (qualitative), structured professional judgement, admission, and secure services. Twelve quantitative articles (published 2007–2020) were identified. SPJ-informed guidance included were the DUNDRUM-1, DUNDRUM-2, DUNDRUM-3, DUNDRUM-4, and the HCR-20. While findings were variable, the overall pattern indicated that ratings suggestive of more problems were associated with increased likelihood of admission or movement to higher security levels. There is emerging evidence for the use of SPJ guidance to support admission decision-making. Specifically, it should be used as an adjunct to existing decision-making processes rather than as a replacement for those processes. Further research, both quantitative and qualitative, across a wider range of settings and populations is recommended.</p></div>