Dr. Glogau developed the following chart; which classifies Photo Aging Groups.  It is used in the spa and by physicians when determining which treatments and products to use.

Glogau Classification of Photo Age Groups:

Group	Photo Aging	Age Range	Appearance
I	Mild	25-35 years old	No keratosis, little scarring or wrinkling. Little or no makeup
II	Moderate	35-50 years old	Early wrinkling, mild scarring and/or discoloration. Little makeup
III	Advanced	50-65 years old	Keratosis, wrinkles, discoloration, telangiectasias. Always wears makeup
IV	Severe	65-75 years old	Keratosis, deep wrinkles, skin laxity, discoloration, scarring. Makeup is caked