Objective:To compare the diagnostic usefulness of index tests in the identification of invasive diarrhea. Methods: Combination of qualitative and metanalytic methods. Data identification and study selection: Of 2603 MEDLINE references (1970-1994) and correspondence with tield experts, 81 fulfilled preestablished selection criteria and 25 of them had sufficient data for additional metaanalysis. Extraction of data: During the qualitative review, one author extracted extended information on the diagnostic value of index tests and on methodologic characteristics of primary studies. During the metanalytical phase, all data from the selected articles were extracted by one observer whereas the second reviewer checked them for accuracy. True positive (TPR) and false positive rates (FPR) were calculated with the 2 x 2 contingency table. To compare the diagnostic usefulness of index tests, a summa...