Study of the International Epidemiology of Androgenetic Alopecia in Young Caucasian Men Using Photographs From the Internet.

Background: The epidemiological evaluation of androgenetic alopecia (AGA) is based mainly on direct observation and questionnaires. The international epidemiology and environmental risk factors of AGA in young Caucasian men remain unknown.

Aim: To use photographs and data from the Internet to evaluate severe AGA and generate greater understanding of the international epidemiology of the disorder in young Caucasian men.