Two‐dimensional planimetry for alopecia areata severity evaluation compared with severity of alopecia tool: A pilot study

SALT-P was more clearly correlated with actual surface area than SALT-I. Planimetric surface area measurement could be used as a supplementary method especially in the S1 to S3, suggesting 60 cm2 , 100 cm2 , and 200 cm2 as objective cutoff values to differentiate S1, S2, and S3.