<qa>  What is the average management change across all applications?Cancer treatment and outcome depend largely on the accurate diagnosis and staging of disease. There is extensive data in the literature indicating the importance of PET imaging in accurately characterizing disease, determining stage and sites of recurrent disease in many cancer types. For these indications, it is well documented in the literature that functional imaging with PET exceeds sensitivity, specificity and accuracy of conventional 3-D imaging modalities. The most widely cited reference for the efficacy of PET imaging is: A Tabulated Summary of the FDG PET Literature, published by Gambhir et al, JNM 2001 42: 1S-93S. In this study the average FDG PET sensitivity and specificity across all oncology applications are estimated at 84 based on 18,402 patient studies and 88 based on 14,264 patient studies, respectively. The average management change across all applications is estimated to be 30 based on 5,062 patients. Data was obtained combining 419 total articles and abstracts on studies in which FDG PET was used. Various methods of analysis were applied to these data, which revealed only a small amount of variation in the ratio values. Specifically, the sensitivity of PET ranged from 84 - 87, the specificity ranged from 88 - 93, and the accuracy ranged from 87 - 90. 