The<unk>  is a method of classifying female pattern baldness (androgenic alopecia), and ranges from stages I to III. Stage I begins with thinning on the top of the head. In stage II the<unk>  starts to show. All of the hair at the crown of the head may be lost when the hair loss progresses to stage III. However, the<unk>  is used merely for general categorization. Many women do not actually fit into the<unk>  stages.
Ludwig scale
Mokken scale
Pest House
Tile classification
Nugent score
Fitzpatrick scale
ILO Classification
Levine scale