Table 1. Baseline Characteristics of the AK Cohort^a.

Matching variable	AK cohort, % (n = 220 236)
Year
2009-2010	21.5
2011-2012	19.5
2013-2015	26.2
2016-2017	16.1
2018-2019	16.7
Age group, y
18-49	12.0
50-59	24.3
60-69	33.6
70-79	19.4
≥80	10.7
Sex
Female	52.5
Male	47.5
Race/ethnicity
African American	0.2
Asian American	1.4
Hispanic	4.1
White	89.5
Other or multiple	4.8

Abbreviation: AK, actinic keratosis.

^aGeneral population control patients were matched to patients with AK on year, age, sex, race/ethnicity, and medical center, and they were assigned an index date corresponding to the initial visit date plus 30 days for the patients with AK. Because their distributions of covariates were matched, they are not listed in this table.