Background: Psychiatric intensive care units (PICU) are a potentially expensive component of inpatient services, and exists to care for those patients who cannot be easily contained on ordinary acute wards. However, to date there is little evidence on their efficacy.
Methods: Using data from a previous study of 136 acute psychiatric wards in England (City-128) we examined whether ordinary acute wards having access to a PICU had lower rates of adverse incidents, and modelled behaviours associated with PICU transfer rates.
Results: Controlling for other factors, wards with greater ease of PICU access did not have lower rates of adverse incidents. PICU provision is related in complex ways to the use of seclusion. PICU transfers were associated with seclusion, manual restraint and other severe containment measures, and were triggered by aggression, drug use and absconding.
Conclusions: Transferring patients to a PICU may not be an effective means of reducing adverse incidents on acute wards and may not have appreciable cost benefits. However, PICUs may still produce a range of valued outcomes such as injury reduction, more effective and efficient treatment, greater feelings of security on acute wards, and care for patients within the criminal justice system. Larger and more detailed evaluations using longitudinal data are required.