SALT Score

The severity of Alopecia Areata (AA) is typically measured with the Severity of ALopecia Tool (SALT) Score1,2 .  The SALT Score is computed by measuring the percentage of hair loss in each of the 4 areas of the scalp — the right profile (accounting for 18% of the total scalp area), the left profile (18%), the vertex (40%), and the posterior (24%), see also figure 4 below. By adding the total procentage of hair loss for each region multiplied by the regions relative area, one achieves a composite total score ie the SALT Score. Hair regrowth is reflected by a decrease in the SALT score (eg, complete hair regrowth would confer a SALT score of 0). Below you will find a simple tool that does the SALT SCORE calculation based on hair loss in each of the above mentioned regions.

Definition of the four main scalp areas associated with the SALT Score. A) Right profile region, B) Left profile, C) Vertex region and D) Posterior region. Image copyright: Kirsten Rønholt
Figure 1: Definition of the four main scalp areas associated with the SALT Score.
Image copyright: Kirsten Rønholt site author

 1: Olsen EA, Hordinsky MK, Price VH, Roberts JL, Shapiro J, Canfield D, et al. Alopecia areata investigational assessment guidelines–part ii. National alopecia areata foundation. J Am Acad Dermatol. 2004;51:440–447

2: Olsen EA, Roberts J, Sperling L, Tosti A, Shapiro J, McMichael A, Bergfeld W, Callender V, Mirmirani P, Washenik K, Whiting D, Cotsarelis G, Hordinsky M. Objective outcome measures: Collecting meaningful data on alopecia areata. J Am Acad Dermatol. 2018 Sep;79(3):470-478.e3