Table 2.

The grading system for intracutaneous (intradermal) reactions

Reaction	Numerical grading
Erythema and eschar formation
No erythema	0
Very slight erythema (barely perceptible)	1
Well defined erythema	2
Moderate erythema	3
Severe erythema (beet redness) to eschar formation preventing grading of erythema	4
Oedema formation
No oedema	0
Very slight oedema (barely perceptible)	1
Well defined oedema (edges of area well defined by define raising)	2
Moderate oedema (edges raised approximately 1 mm)	3
Severe oedema (raised more than 1 mm and extended beyond exposure area)	4