Staging of AP is important for selection of patients for clinical trials, c
omparison of results between centers, and the early identification of patie
nts who may benefit from therapeutic intervention or transfer to a speciali
st unit. The acute physiologic assessment and chronic health evaluation (AP
ACHE) II score and the multiple factor scoring systems are widely used for
the first two indications and, of these, the APACHE II score provides the b
est accuracy at an early stage in the course of the illness. At present, ho
wever, no system provides sufficient predictive power to facilitate clinica
l decision making. At a time of increasing pressure to involve specialist u
nits at an early stage in the management of these patients, there remains a
pressing need to identify a system for early staging of AP.