A Cluster Randomized Trial of Sun Protection at Elementary Schools Results from Year 2

Background: Elementary schools are one potential venue for sun protection interventions that reduce childhood sun exposure. Purpose: To assess Year-2 results from a cluster randomized trial promoting hat use at schools. Design: Block randomization was used to assign intervention/control status to participating schools. Data were collected from 2006 to 2008 and analyzed in 2007-2010. Setting/participants: Of the 24 schools in the School District of Hillsborough County, Florida enrolled, 4th-graders were targeted in the first year and followed through their 5th-grade year. Intervention: Classroom sessions were conducted to improve sun protection knowledge, foster more positive attitudes about hat use, and change the subjective norm of wearing hats when at school. Main outcome measures: Year-2 outcomes assessed included hat use at school (measured by direct observation), hat use outside of school (measured by self-report) and skin pigmentation and nevi counts (measured for a subgroup of 439 students). Results: The percentage of students observed wearing hats at control schools remained unchanged during the 2-year period (range 0%-2%) but increased significantly at intervention schools (2% at baseline, 41% at end of Year 1, 19% at end of Year 2; p<0.001 for intervention effect). Measures of skin pigmentation, nevi counts, and self-reported use of hats outside of school did not change during the study period. Conclusions: This intervention increased use of hats at school through Year 2 but had no measurable effect on skin pigmentation or nevi. Whether school-based interventions can ultimately prevent skin cancer is uncertain.