Supplementary Methods for phototrichogram technique and hair diameter measurement

This dataset supports the study on hair diameter diversity (HDD) as a diagnostic indicator for androgenetic alopecia (AGA). It includes methodological details on how phototrichogram images were captured and analyzed. Magnified images of the vertex and occiput were obtained using Folliscope® 5.0 at 50x–85x magnification. For accurate quantification, images were further analyzed using Image J software with pixel-level precision. Hair diameters were measured 350–450 µm from the scalp surface to reflect natural hair thickening patterns, and overlapping or marginal hairs were excluded.