摘要
PURPOSE: The Physiologic and Operative Severity Score for the enUmeration of M ortality and morbidity (POSSUM), Portsmouth revision (p)-POSSUM, and colorectal (Cr)-POSSUM scoring systems were developed as audit tools for comparing outcomes in surgical and colorectal patients on the basis of operati ve risk assessment. The aim of this study was to evaluate the applicability of t hese systems to a cohort of colon cancer patients undergoing surgery in the Unit ed States. METHODS: POSSUM factors from 890 consecutive patients undergoing majo r surgical procedures for colon cancer in nine United States hospitals over a tw o-year period from January 2000 through December 2001 were prospectively collec ted. The observed over the expected hospital mortality was compared by means of the POSSUM, p-POSSUM, and Cr-POSSUM scoring systems. The effect of missing dat a on the utility of this process for outcome assessment was assessed with three methods for data imputation. RESULTS: The number of resections per institution r anged from 13 to 437. The observed mortality rate ranged from 0.8 percent to 15. 4 percent among the institutions, with an overall operative mortality of 2.3 per cent. The POSSUM, p-POSSUM, and Cr-POSSUM predicted mortality was 10.7 percent , 11.2 percent, and 4.9 percent, respectively. The POSSUM and p-POSSUM models o verpredicted mortality in all institutions (P < 0.01), whereas the Cr-POSSUM de monstrated an observed over expected hospital mortality ratio of >1 in three ins titutions. The calculations were unaffected by the various methods of inserting missing data. CONCLUSION: An apparent overprediction of mortality for colon canc er resection was evident with all three POSSUM variants. This implies that a cal ibration process is required for use of these variants in the United States heal th care system. Missing data may be treated as normal values without influencing outcome. The Cr-POSSUM appeared to be the most promising audit tool for colore ctal cancer surgery; however, it will require further refinement to provide proc ess control graphs for identification of potential outliers and improvement in t he quality of care in the United States.
PURPOSE: The Physiologic and Operative Severity Score for the enUmeration of M ortality and morbidity (POSSUM), Portsmouth revision (p)-POSSUM, and colorectal (Cr)-POSSUM scoring systems were developed as audit tools for comparing outcomes in surgical and colorectal patients on the basis of operati ve risk assessment. The aim of this study was to evaluate the applicability of t hese systems to a cohort of colon cancer patients undergoing surgery in the Unit ed States. METHODS: POSSUM factors from 890 consecutive patients undergoing majo r surgical procedures for colon cancer in nine United States hospitals over a tw o-year period from January 2000 through December 2001 were prospectively collec ted. The observed over the expected hospital mortality was compared by means of the POSSUM, p-POSSUM, and Cr-POSSUM scoring systems. The effect of missing dat a on the utility of this process for outcome assessment was assessed with three methods for data imputation. RESULTS: The number of resections per institution r anged from 13 to 437. The observed mortality rate ranged from 0.8 percent to 15. 4 percent among the institutions, with an overall operative mortality of 2.3 per cent. The POSSUM, p-POSSUM, and Cr-POSSUM predicted mortality was 10.7 percent , 11.2 percent, and 4.9 percent, respectively. The POSSUM and p-POSSUM models o verpredicted mortality in all institutions (P < 0.01), whereas the Cr-POSSUM de monstrated an observed over expected hospital mortality ratio of >1 in three ins titutions. The calculations were unaffected by the various methods of inserting missing data. CONCLUSION: An apparent overprediction of mortality for colon canc er resection was evident with all three POSSUM variants. This implies that a cal ibration process is required for use of these variants in the United States heal th care system. Missing data may be treated as normal values without influencing outcome. The Cr-POSSUM appeared to be the most promising audit tool for colore ctal cancer surgery; however, it will require further refinement to provide proc ess control graphs for identification of potential outliers and improvement in t he quality of care in the United States.
