In a randomized, controlled trial of the effect on solar keratoses of daily use of a broad-spectrum sunscreen cream with a sun-protection factor of 17 in 588 people 40 years of age or older in Australia during one summer, the subjects applied either a sunscreen cream or the base cream minus the active ingredients of the sunscreen to the head, neck, forearms and hands 1. The mean number of solar keratoses increased by 1.0 per subject in the base-cream group and decreased by 0.6 in the sunscreen group (difference, 1.53; 95% confidence interval, 0.81 to 2.25). The sunscreen group had fewer new lesions (rate ratio, 0.62; 95% confidence interval, 0.54 to 0.71) and more remissions (odds ratio, 1.53; 95% confidence interval, 1.29 to 1.80) than the base-cream group. There was a dose-response relationship.
Primary/Secondary Keywords