Tice, R., Haneke, K., Goldsworthy, T., Margolin, B., and W. Stokes. Analysis of the Murine Local Lymph Node Assay: Intralaboratory and Interlaboratory Variability, Stimulation Index as a Measure of the Dermal Irritancy, and Performance Characteristics. ATLA. 1999. 27: 356.

To evaluate the repeatability and reproducibility of the murine local lymph node assay (LLNA, an allergic contact dermatitis test) the interlaboratory and intralaboratory consistency statistics (h and k, respectively; American Society for Testing and Materials [ASTM] Guideline E 691-92) were calculated for validation studies testing multiple chemicals in several laboratories. The analysis indicated a lack of significant intralaboratory and interlaboratory variability in the dose calculated to induce a three-fold increase in the stimulation index (SI). To assess the appropriateness of using an SI of three as the decision criteria for identifying an irritating compound, LLNA results based on SI values of 2.0, 2.5, 3.0, 3.5 and 4.0 were compared with guinea-pig or human results. Compared to data generated by using guinea-pig tests, the accuracy of the LLNA was highest (79%; 83/105 compounds tested) when an SI of three was used as the decision criteria, and overall performance results supported the three-fold increase as an adequate indicator of the sensitising ability of chemicals. Assay performance was determined by comparing LLNA results to results obtained for guinea-pigs or humans. The accuracy of the LLNA was 89% (86/97) when compared to results from all guinea-pig tests. The performance of the LLNA and the GPMT/BA was similar when each was compared to human maximisation test plus human patch test allergen results.