Whiteley M S, Prytherch D R, Higgins B, Weaver P C, Prout W G
Department of Surgery, Queen Alexandra Hospital, Portsmouth, UK.
Br J Surg. 1996 Jun;83(6):812-5. doi: 10.1002/bjs.1800830628.
POSSUM (Physiological and Operative Severity Score for the enUmeration of Morbidity and mortality) has been studied as a possible surgical audit system for a 9-month interval using a sample of 28 per cent of the general surgical workload. Mortality or survival was analysed as an endpoint. In this sample the published POSSUM predictor equation for mortality overpredicted deaths by a factor of more than two. The bulk of the overprediction occurred in the group at lowest risk (predicted mortality 10 per cent or less), in which death was overpredicted by a factor of six. This is the most important group for audit purposes since it contains the majority of surgical patients and is composed of fit patients undergoing minor surgery. The published predictor equation for mortality returns a minimum predicted mortality of 1.08 per cent, clearly far higher than that expected for a fit patient having minor surgery. Logistic regression was done on a set of 1485 surgical episodes to generate a local predictor equation for mortality. This process gave a predictor equation that fitted well with the observed mortality rate and gave a minimum predicted risk of mortality of 0.20 per cent. The previously published POSSUM predictor equation for mortality performed badly when tested using a standard test of goodness of fit for logistic regression and must be modified.
POSSUM（生理和手术严重程度评分系统，用于计算发病率和死亡率）已作为一种可能的手术审计系统进行研究，该研究为期9个月，样本涵盖普通外科工作量的28%。将死亡率或生存率作为终点进行分析。在这个样本中，已发表的POSSUM死亡率预测方程对死亡人数的预测高估了两倍多。大部分高估发生在风险最低的组（预测死亡率为10%或更低），其中死亡人数被高估了六倍。对于审计目的而言，这是最重要的组，因为它包含了大多数外科手术患者，并且由接受小手术的健康患者组成。已发表的死亡率预测方程得出的最低预测死亡率为1.08%，明显远高于接受小手术的健康患者的预期死亡率。对一组1485例手术病例进行逻辑回归分析，以生成死亡率的局部预测方程。这一过程得出的预测方程与观察到的死亡率拟合良好，得出的最低预测死亡风险为0.20%。当使用逻辑回归拟合优度的标准测试进行检验时，先前发表的POSSUM死亡率预测方程表现不佳，必须进行修改。
