How did sun protection compare for people who spent 3A1 2 hours on a sunny beach with some under an umbrella and others wearing SPF 100 sunscreen? A new article published online by JAMA Dermatology reports neither method used alone completely prevented sunburn, although the SPF 100 sunscreen was more efficacious in the randomized clinical trial. Hao Ou-Yang, Ph.D., of Johnson & Johnson Consumer, Inc., Skillman, N.J., and coauthors used actual conditions to monitor the sun protection of a standard beach umbrella compared with the high SPF sunscreen.