RAST, skin and nasal tests and the history in grass pollen allergy.

A comparison of the RAST (Phadebas), skin prick test, nasal test and a history of hay fever was made in 141 subjects, eighty-seven being prick test positive, with three concentrations of extracts of Sweet vernal (Anthoxanthum odoratum), Cocksfoot (Dactylis glomerata), Meadow fescue (Festuca elatior), Rye (Lolium perenne), Timothy (Phleum pratense), Meadow (Poa pratensis). In adequate concentration any of the species extracts would have sufficed for skin tests, with Cocksfoot pollen the most potent. Correlations found were: positive RAST/prick test, 98%; positive prick test/RAST, 89%; positive RAST/nasal test, 75%, and the higher the RAST the closer the correlation and the higher the nasal sensitivity; nasal test positive/RAST negative, 17%; positive history/RAST, 91%; positive history/prick test, 92%.