Sunscreen application technique amongst patients with a history of skin cancer

Data on how patients with a history of skin cancer apply sunscreen are lacking.

To characterize (1) gender differences in sunscreen application technique (quantity used, anatomic site coverage, and time allocated) and (2) differences in sunscreen application to unaffected skin versus previous skin cancer sites.

Subjects with a history of skin cancer were asked to apply sunscreen to their head as they normally would. The amount of sunscreen used and application time were recorded. Before and after photos were taken. Using Wood's lamp lighting, an anatomic site coverage score was rated on an ordinal scale (1 = 0-25%, 2 = 26-50%, 3 = 51-75%, 4 = 76-100% coverage).

Males used 530 mg more sunscreen (p < 0.001) and applied approximately 5 mg/cm² of sunscreen versus women, who applied 2 mg/cm². The average coverage score was 3.27. Males were 7.61 times more likely to adequately apply sunscreen to the ears (p = 0.001). No differences were noted in application times. Coverage scores were similar for unaffected skin and previous skin cancer sites.

Observations in a controlled setting may not reflect usual sunscreen application practices.

Overall, skin cancer survivors of both genders effectively applied sunscreen in line with recommended quantity guidelines, but men were significantly better at protecting their ears.