Sensitivity and predictive value positive measurements for public health surveillance systems.

Two important measurements for the evaluation of a public health surveillance system are sensitivity and predictive value positive (PVP). The computation of sensitivity and PVP for a public health surveillance system, however, can be complicated by the absence of an appropriate gold standard. In addition, there are few references for the computation of sensitivity and PVP for a surveillance system. To determine how these attributes of evaluation have been reported in epidemiologic literature, I review papers that report sensitivity and PVP for public health surveillance systems. Of the 31 papers that met selection criteria, 21 (68%) included either a reference for the computation or a definition of the attributes, whereas 18 (58%) reported both attributes. All 31 papers reported sensitivity, and among the 31 papers, 24 (77%) reported more than one sensitivity measurement. Among the 18 papers that reported at least PVP, 13 (72%) reported more than one PVP measurement. This review provides guidance in computing sensitivity and PVP for a public health surveillance system.