Previous case-control studies have suggested that sunscreen use is associated with an increased risk of melanoma (see "Comment" section). Because high nevus counts are a predictor of melanoma, the objective of this study was to determine whether the number of melanocytic nevi in European, white children was associated with their sunscreen use. In this cohort study, the patient population consisted of 631 children in their first year of primary school in 4 European cities. The whole-body and site-specific counts of nevi 2 mm or larger were performed on each child. Independently, parents were interviewed regarding host characteristics (eg, skin type and eye color), sun exposure, sunscreen use, and physical sun protection with clothing.