The data reported by Guarrera et al are actually in agreement with our results. Although we found a good correlation between hair density and the Hamilton classification, we agree that the Hamilton scale is often difficult to use in clinical practice and does not represent a precise method to classify patients. Our clinical hair density scale, which is easy to use, represents a complementary tool for the clinician and can be very useful to accurately follow-up AGA evolution in a given patient.
de Lacharrière O. Do Hair Density and Thickness Correlate With the Hamilton Scale?—Reply. Arch Dermatol. 2002;138(8):1099. doi:10.1001/archderm.138.8.1098