Conclusions P-POSSUM was the most accurate model for predicting post-operative mortality after colorectal cancer surgery .
The original POSSUM model was accurate in predicting post-operative complications
Introduction The Physiological and Operative Severity Score for the enUmeration of Mortality and morbidity  ( POSSUM ) model and its Portsmouth ( P-POSSUM ) and colorectal ( CR-POSSUM ) modifications are used extensively to predict and audit post-operative mortality and morbidity .
This aim of this systematic review was to assess the predictive value of the POSSUM models in colorectal cancer surgery .
Predicting post-operative mortality in patients undergoing colorectal surgery using P-POSSUM and CR-POSSUM scores: a prospective study
Introduction POSSUM and its variants Portsmouth POSSUM ( P-POSSUM ) and Colorectal POSSUM ( CR-POSSUM ) equations were derived from a heterogeneous general surgical population , which have been used successfully to provide risk-adjusted operative mortality rates . CR-POSSUM utilises fewer parameters , allowing ease of use . The aim of this study was to predict the mortality outcome in colorectal surgery using these scoring systems compared to the observed mortality and to devise a new scoring system with improved accuracy . Methods The study was conducted prospect ively on all consecutive patients requiring elective and emergency colorectal surgery between April 2002 and May 2005 . The outcome parameter was defined as 30-day mortality . The observed mortality was compared with predicted mortality by the scoring systems . Hosmer and Lemeshow test was used to assess statistical accuracy of POSSUM . Results Eight hundred ninety-nine patients underwent colorectal surgery during the study period . There were 619 elective and 281 emergency patients .  Observed 30-day mortality rate was 9 % , compared with predicted mortality rate of 13.5 % with POSSUM , 5 % with P-POSSUM and 9.5 % with CR-POSSUM . Conclusion POSSUM ’s mortality rate was overestimated , while P-POSSUM ’s mortality rate was underestimated . CR-POSSUM , the simplest system of all three , most accurately predicted mortality in our unit
Conclusions P-POSSUM was the most accurate model for predicting post-operative mortality after colorectal cancer surgery .
The original POSSUM model was accurate in predicting post-operative complications
Introduction The Physiological and Operative Severity Score for the enUmeration of Mortality and morbidity  ( POSSUM ) model and its Portsmouth ( P-POSSUM ) and colorectal ( CR-POSSUM ) modifications are used extensively to predict and audit post-operative mortality and morbidity .
This aim of this systematic review was to assess the predictive value of the POSSUM models in colorectal cancer surgery .