Table 1 Criteria for human skin patch test by International Contact Dermatitis Research Group
Symbol | Score | Result |
|---|---|---|
− | 0 | Negative |
± | 0.5 | Doubtful or slight reaction and erythema |
+ | 1 | Erythema + Induration |
++ | 2 | Erythema + Induration + Vesicle |
+++ | 3 | Erythema + Induration + Bullae |