Evaluation of tests for infectious mononucleosis through proficiency testing

Two standard tests for infectious mononucleosis (the Davidsohn differential and the ox cell hemolysin test) and ten slide tests; Monotest (Wampole), Monospot (Ortho), IM Kit (Micro. Res. Corp.) Monosticon (Organon), Diagluto IM (Beckman), Monosticon Dri-Dot (Organon), Bacto-Hetrol (Difco), Mono-Diff (Wampole), Monophile (Bio-Diagnostic Systems) and Rythrotox (BMC) were evaluated as they were used in 50 laboratories within the State of Utah and by two referee laboratories outside the state. The state proficiency testing program for infectious mononucleosis was modified so that the desired evaluation survey data could be obtained. Sensitivity, specificity, reproducibility (within and between shipments) and percent agreement with target results were determined for each test; factors which might have affected the test results were evaluated to determine which were correlated with good performance.