Positive shick’s test indicates that person is :
Immune to diphtheria
Hypersensitive to diptheria
Susceptible to diptheria
Carrier of diphtheria
Shick’s test

Intradermal test which provide information regarding :

a. Immune status, b. Hypersensitivity & susceptibility to diptheria toxin before giving active immunization.

 In one arm toxin is injected (test arm) and in other arm heat inactivated toxin is injected (control arm).