A photonumeric scale for the assessment of cutaneous photodamage.

BACKGROUND AND DESIGN The assessment of the severity of cutaneous photodamage and its response to treatment is an impractical consideration for most practitioners without extensive experience or recourse to high-quality, standardized, baseline photographs. To address this problem, a nine-point photonumeric standard scale was developed using photographs of subjects representing grades of photodamage from none to severe. This scale was formally tested in a side-by-side comparison with a conventional and widely used written descriptive scale. A panel of seven graders used both scales to score two sets of 25 photographs of photodamaged individuals, and the intergrader agreement and repeatability for the scales were calculated. RESULTS The photonumeric scale demonstrated significantly greater agreement between graders than did the descriptive scale (chance-corrected agreements of 0.31 and 0.11, respectively, P less than .0001) with no significant difference in repeatability between the two methods. CONCLUSIONS This study demonstrates that the photonumeric standard scale is superior to existing methodology in the accurate assessment of cutaneous photodamage and would be a useful adjunct to studies of the efficacy of skin repair agents for this indication.