Modelling in-patient bed usage behaviour in a department of geriatric medicine.
The flow of patients through geriatric hospitals has been previously described in terms of acute and long-stay states where the bed occupancy at a census point is modelled by a mixed exponential model. Using data for sixteen years the model was fitted to successive annual census points, in order to provide a description of temporal trends. While the number of acute patients has remained fairly stable during the period, the model shows that there has been a decrease in the number of long-stay patients. Mean lengths of stay in our geriatric hospital before death or discharge have decreased during the study period for both acute and long-stay patients. Using these fits of the mixed exponential model to census data, a method is provided for predicting future turnover of patients. These predictions are reasonably good, except when the turnover patterns go through a period of flux in which assumption of stability no longer holds. Overall, a methodology is presented which relates census analysis to the behaviour of admission cohorts, thus producing a means of predicting future behaviour of patients and identifying where there is a change in patterns.
McClean
S
S
Department of Mathematics, University of Ulster, Coleraine, Northern Ireland.
Millard
P
P
D000368:Aged; D001509:Bed Occupancy / Q000639:trends*; D006299:Health Services for the Aged; D006801:Humans; D007902:Length of Stay; D008962:Models, Theoretical