It has been difficult to accurately determine the prevalence of male pattern hair loss. This study, conducted with a community-based sample of healthy males 18-49 years old, found that hair loss increased with increasing age, ranging from 16% for men 18–29 years of age to 53% of men 40–49.
The evaluation was made through several, aggregated measures; participants completed a brief questionnaire self reporting degree of hair loss, general health-related quality of life (HRQL) and hair-loss-specific measures. A trained observer also rated each participant using standardized classification for male pattern hair loss.
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