Validity of a Sun Safety Diary Using UV Monitors in Middle School Children

Abstract

This article describes a validity study conducted among middle school students comparing self-reported sun safetybehaviorsfroma diarywith readingsfromultraviolet(UV)monitorswornondifferentbodysites. The UV monitors are stickers with panels that turn increasingly darker shades of blue in the presence of increasing amounts of UV light. Three schools participated ( N = 527). Statistically significant associations were found between self-reported behaviors and the UV monitor measurements, with Kendall's tau b's ranging from 0.400 to 0.823. Multiple regression was performed and indicator variables created separately for arm ( R = .12) and leg ( R = .49) coverage by protective clothing. The effect of time spent outdoors on the UV monitor measure was attenuated when the students reported having the corresponding body site covered with clothing. Self-reported shade was not a significant predictor of UV monitor change. Overall, the results provide evidence of validity of students' self-reports of time outdoors and protective clothing use.