Gambino Blasé
J Gambl Stud. 2006 Dec;22(4):393-404. doi: 10.1007/s10899-006-9025-5.
The difference between test accuracy and predictive accuracy is presented and defined. The failure to distinguish between these two types of measures is shown to have led to a misguided debate over the interpretation of prevalence estimates. The distinction between test accuracy defined as sensitivity and specificity, and predictive accuracy defined as positive and negative predictive value is shown to reflect the choice of the denominator used to calculate true positive, false positive, false negative, and true negative rates. It is further shown that any instrument will tend to overestimate prevalence in low base rate populations and underestimate it in those populations where prevalence is high. The implications of these observations are then discussed in terms of the need to define diagnostic thresholds that have clinical and policy relevance.
文中介绍并定义了检验准确性与预测准确性之间的差异。结果表明，未能区分这两种测量类型导致了对患病率估计解释的误导性争论。检验准确性（定义为敏感性和特异性）与预测准确性（定义为阳性预测值和阴性预测值）之间的差异反映了用于计算真阳性、假阳性、假阴性和真阴性率的分母的选择。进一步表明，任何工具在低基础率人群中往往会高估患病率，而在患病率高的人群中则会低估患病率。然后，根据定义具有临床和政策相关性的诊断阈值的必要性，讨论了这些观察结果的意义。
