... Whiteley MS, Higgins B, Weaver PC, Prout WG, Powell SJ: POSSUM and Portsmouth POSSUM for predicting mortality Physiological and Operative Severity Score for the enUmeration of Mortality and morbidity ... P-POSSUM, Portsmouth Modification of Physiological and Operative Severity Score for the enumeration of Mortality and morbidity; HOP, Head of pancreas; CBD, Common Bile Duct; SD, Standard Deviation ... Society of Anaesthesiologists) score, APACHE (Acute Physiology and Chronic Health Evaluation), POSSUM (Physiological and Operative Severity Scoring System for Enumeration of Morbidity and Mortality) ...