The effect of an ultraviolet photography educational exercise on sunscreen application.

Abstract

e22506 Background: Sun exposure is a known risk factor for skin cancer development. Sun protection factor (SPF) is based on an application of 2 mg/cm2 of facial surface area (FSA). Studies demonstrate that most people do not apply a sufficient volume to achieve the intended SPF, thus overestimating their sun protection. Ultraviolet photography (UVP) is easily performed by placing an inexpensive UV filter over a digital camera lens. Chemical and physical sunscreen appear metallic black and blue, respectively, under UV light, thus helping to visualize sunscreen application. We sought to determine if visualizing application with UVP increases the volume of sunscreen applied and to investigate the effect of demographic factors and sunscreen type (physical and chemical) on the results of the intervention. Methods: Participants were recruited from June to August 2022. Subjects were randomized to either physical or chemical sunscreen for the first round of sunscreen application. Using a mirror, subjects applied sunscreen as they normally would. Subjects were then shown a UV photo that helped visualize the extent of sunscreen application. With a clean face, the process was repeated with the other sunscreen type (physical or chemical), such that each subject applied both types by the end of the study (round 2). Sunscreen bottles were weighed before and after applications to calculate the volume of sunscreen applied. Statistics were performed in RStudio version 1.4.1717, a language and environment for statistical computing. Results: 30 subjects (ages 18 to 88, Fitzpatrick skin type I-V) were enrolled. A greater percentage of participants applied > 2mg/cm2 from round 1 to round 2 (23% vs 36%). Mean application volume significantly increased from round 1 to round 2 (1.46 SD = 0.936 to 2.15 SD = 1.91, p = 0.0256). Subjects in the “chemical first” group applied a greater amount in round 2 (p< 0.001), however the same was not true in the “physical first” group. Mean sunscreen applied did not significantly differ between chemical and physical in round 1 (p = 0.187). There were no significant differences observed in sunscreen application across race, gender, skin type, and age. Conclusions: The volume of application increased during round 2, indicating that UVP may be an effective intervention to increase the volume of sunscreen application. Differences between the chemical first and physical first groups indicate the intervention may be more suited to teach the application of chemical sunscreen, which appears darker on UVP. Lack of difference between sunscreen types in round 1 suggests there was negligible pre-intervention bias in application behaviors. Overall, most subjects applied less than the recommended amount of sunscreen in both rounds, suggesting that additional counseling is paramount to ensuring proper sunscreen utilization among the public to prevent skin malignancy.