Cookies on this website

We use cookies to ensure that we give you the best experience on our website. If you click 'Accept all cookies' we'll assume that you are happy to receive all cookies and you won't see this message again. If you click 'Reject all non-essential cookies' only necessary cookies providing core functionality such as security, network management, and accessibility will be enabled. Click 'Find out more' for information on how to change your cookie settings.

BACKGROUND: A lack of consensus exists concerning how to identify "heavy users" of inpatient mental health services. AIM: To identify a statistical approach that captures, in a clinically meaningful way, "heavy" users of inpatient services using number of admissions and total time spent in hospital. METHODS: "Simple" statistical methods (e.g. top 2%) and data driven methods (e.g. the Poisson mixture distribution) were applied to admissions made to adult acute services of a London mental health trust. RESULTS: The Poisson mixture distribution distinguished "frequent users" of inpatient services, defined as having 4 + admissions in the study period. It also distinguished "high users" of inpatient services, defined as having 52 + occupied bed days. Together "frequent" and "high" users were classified as "heavy users". CONCLUSIONS: Data driven criteria such as the Poisson mixture distribution can identify "heavy" users of inpatient services. The needs of this group require particular attention.

Original publication




Journal article


J Ment Health

Publication Date





455 - 460


Inpatient services, heavy use, length of stay, readmission, statistical methodology, Adolescent, Adult, Bed Occupancy, Female, Hospitals, Psychiatric, Humans, Inpatients, Length of Stay, London, Male, Mental Health Services, Patient Admission, Patient Readmission, Poisson Distribution, Young Adult