Primed lymphocyte typing (PLT): dichtomizing responses into "positives" and "negatives".

In primed lymphocyte typing (PLT), it will often be useful to divide the test cells for any given reagent into a positive and a negative group. Some general problems in PLT analysis are discussed here. The author describes a model for PLT data, to provide a conceptual framework, and suggests a statistical procedure based on the model.