The Dick test, performed to determine susceptibility to scarlet fever, consists of the intradermal injection of 0.1 cc. of the commercial toxin. The development of a nonindurated erythematous area measuring 10 by 10 mm. or more indicates susceptibility to the disease. To account for the discrepancies and difficulties that workers have experienced with the test, the Dicks1 have listed a series of common sources of errors in the technic. One source of error listed is the subcutaneous instead of the intracutaneous injection of the toxin.
The purpose of the present investigation was to determine the validity of this point by actual trial, the work being carried out at the suggestion of Dr. Silber C. Peacock. The children tested were those admitted to the Children's Memorial Hospital for tonsillectomy and adenoidectomy. As a group they represented the average children of a dispensary clientele. They were selected by the staff of