Background and Objectives：TIncidence of sensitization with several air-born pollens were studied in Korea mainly by direct intradermal test, and in some cases completed with provocation test in conjunctiva and nasal mucosa. The tests were performed on 313 patients with suspected allergy and on 299 control person. The pollen used were pine, rose and carpinus. For the comparative study, house dust was also used. In direct skin test 0.05ml of allergen extract of 1 : 1000 dilution was injected intracutaneously. The reading of the result was made 15-20 minutes after the injection. The author proposes the following criteria of intradermal skin test with inhalant allergens ; (-) : No reaction at all. (†) : Diameter less than 10mm, (††) : Diameter 10mm~20mm, (†††) : Diameter 20mm~30mm, (††††) : Diameter above 30mm. Following these standards, positive skin reactions for one or more allergens were observed in 61.9% of the allergy-patients(allergic rhinitis and a few asthma cases), and 22.2% of the normal control persons also showed positive reactions for one or more allergens. The positive reactions in the whole material were distributed in the four groups as follows : 

The positive reactions in the whole material distributed on the different allergens were as follows : 

Provocation test in conjunctiva and nasal mucosa were carried out in some cases with the extracts of pollens. Both of these tests showed positive reaction in rather few cases. In one patient with bronchial asthma a typical attack was elicted by the provocation test in the nasal mucosa and emergency treatment was necessary. A comparative study between Korean and Scandinavian house dust performed on 91 allergy patients showed 58.2 and 17.5% positive reactions respectively.