Inter- and Intra-physician variation in quantifying actinic keratosis skin photodamage

Abstract

We investigated the variations in physician evaluation of skin photodamage based on a published photodamage scale. Of interest is the utility of a 10-level scale ranging from none and mild photodamage to actinic keratosis (AK). The dorsal forearms of 55 adult subjects with various amounts of photodamage were considered. Each forearm was independently evaluated by 15 board-certified dermatologists according to the Global Assessment Severity Scale ranging from 0 (less severe) to 9 (the most progressed stage of skin damage). Dermatologists rated the levels of photodamage based upon the photographs in blinded fashion. Results show substantial disagreement amongst the dermatologists on the severity of photodamage. Our results indicate that ratings could be more consistent if using a scale of less levels (5-levels or 3-levels). Ultimately, clinicians can use this knowledge to provide better interpretation of inter-rater evaluations and provide more reliable assessment and frequent monitoring of high-risk populations.

Figure 1:

Examples of mild, moderate, severe photodamage analyzed by clinical dermatologists.

Figure 2:

Physician scores (0-9) associated with each arm, numbers along rows indicate patient number along with left (“L”) or right (“R”) arm. Columns indicate which physician evaluated the patient. Colors and umbers in each cell are the score given.

Figure 3:

a) Physician clinical scores of skin damage. b) Range of scores from dermatologists. Modified from (Travers, et al., 2019) [7].

Figure 4:

Physician scores (0-9) associated with each arm, numbers along rows indicate patient number along with left (“L”) or right (“R”) arm. Columns indicate which dermatologist evaluated the patient. Colors and umbers in each cell are the score given. Notably, subject 51’s right arm was examined 3 times by all dermatologists (2 repeated evaluations). The original scores for 51, R is repeated twice in b) to facilitate readability.