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 .
Comparison of POSSUM and P-POSSUM for risk-adjusted audit of patients undergoing emergency laparotomy.
BACKGROUND The Physiological and Operative Severity Score for Enumeration of Mortality and Morbidity  ( POSSUM ) scoring system , derived from a heterogeneous population , has been used successfully as an audit tool , but it has appeared to over-predict mortality in low-risk groups for which an alternative system , the Portsmouth predictor equation for mortality ( P-POSSUM ) was design ed and used successfully . In this prospect i ve study , we compared these two equations in predicting death and tested their validity in predicting morbidity and mortality in patients undergoing emergency laparotomy in a tertiary hospital . METHODS Eighty-two patients who underwent emergency laparotomy were included in this study .  Actual morbidity and mortality rates were compared with the predicted mortality and morbidity rates using both POSSUM and P-POSSUM equations by linear regression and exponential methods of analysis . RESULTS POSSUM equation significantly over-predicted both morbidity and mortality when linear regression analysis was used , but predicted well when exponential analysis was used . Prediction of mortality by P-POSSUM was good using both linear and exponential analyses , and exponential method was better than linear regression analysis . CONCLUSION P-POSSUM is a better equation than POSSUM in predicting mortality , and exponential method is better than linear regression analysis . Both equations are useful tools for risk-adjusted surgical audit of patients undergoing emergency laparotomy
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 .