In Reply.—Drs Longo, Strinati, and Tedesco are concerned with the relative diagnostic sensitivity and specificity of prick vs intradermal skin tests. We would agree with them that the quality of the allergenic extract is critical to this question. This is the reason that we chose to use extracts from the same manufacturer in both in vitro tests and for skin testing since we felt that this would provide a more valid comparison of the methods without the compounding variable of different extracts. We also agree that with high-quality extracts prick testing is the preferred method in children, and we have published improvements to the technique for young children.1 Drs Longo, Strinati, and Tedesco have, however, misinterpreted the data concerning the number of positive and negative prick and intradermal tests. When we stated that there were four patients with negative prick tests and positive intradermal and in vitro tests,