Few studies have described clinical characteristics of patients subject to an involuntary detention in an Irish context. The Irish Mental Health Act 2001 makes provision under Section 23(1), whereby a person who has voluntary admission status can be detained.

This study aimed to describe all involuntary admissions to St Patrick’s University Hospital (SPUH) (2011–2013) and to evaluate clinical characteristics of voluntary patients who underwent Mental Health Act assessment during 2011 to determine differences in those who had involuntary admission orders completed and those who did not.

All uses of Mental Health Act 2001 within SPUH 2011–2013 were identified. All uses of Section 23(1) during 2011 were reviewed and relevant documents/case-notes examined using a pro forma covering clinical data, factors recognized to influence involuntary admissions and validated scales were used to determine diagnoses, insight, suicide and violence risk.

Over 2011–2013, 2.5–3.8% of all admissions were involuntary with more detained after use of Section 23(1) than Section 14(2). The majority of initiations of Section 23(1) did not result in an involuntary admission (72%), occurred out of hours (52%) and many occurred early after admission (<1 week, 43%). Initiation of Section 23(1) by a consultant psychiatrist (p=0.001), suicide risk (p=0.03) and lack of patient insight into treatment (p=0.007) predicted conversion to involuntary admission.

This study predicts a role for patient insight, suicide risk and consultant psychiatrist decision making in the initiation of Mental Health Act assessment of voluntary patients. Further data describing the involuntary admissions process in an Irish setting are needed.