Three prick test methods were compared in the diagnosis of mite allergy--the Morrow Brown standardized needle, the Multi-test device and a modified prick test. They were compared with the intradermal test and with specific IgE antibodies measured by RAST. Thirty patients and 10 control subjects were tested. The intradermal test was always positive in patients but induced two false positive reactions. All prick test methods gave false negative reactions. The Multi-Test device produced intermediate reactions between prick test and intradermal test.