RESUMO
OBJECTIVE: to evaluate the association between phenotype and sun sensitivity factors, sun protection behavior, ethnicity and the area of residence in school-aged children. DESIGN: a cross-sectional study in the framework of a survey of children using a self-administered questionnaire to be filled in by parents. SETTING AND PARTICIPANTS: 56390 children attending primary schools located in the Italian provinces of Brindisi, Rome, Forlì and Genova, in the period between 1998-2002. MAIN OUTCOME MEASURES: Odds Ratios (ORs) and their relative 95% Confidence Intervals (95% CI) are to be computed through univariate and multivariate logistic regression models. RESULTS: "FOTO positive" phenotype, a proxy variable of the fair phenotype, was directly and significantly associated with the tendency to sunburn (OR 4.75; 95% CI 4.54-4.96), the use of sunscreens (OR 1.79; 95% CI 1.63-1.97), the number of grandparents born in the northern areas (OR 1.63; 95% CI 1.45-1.83, for four northern grandparents versus none), the presence of freckles on the face (OR 1.62; 95% CI 1.53-1.72) and of naevi on the left forearm (OR 1.20; 95% CI 1.15-1.26). A positive association was also found for the residence in the northern areas using the area of Brindisi as the reference category, (Rome: OR 1.02; 95% CI 0.95-1.10; Forlì: OR 1.05; 95% CI 0.96-1.15; Genova: OR 1.16; 95% CI 1.08-1.26); the ORs increase with latitude, as does the incidence rate of melanoma in Italy. An inverse association was observed with the male sex (OR 0.92; 95% CI 0.88-0.96), the increase of school-class level (OR 0.65; 95% CI 0.60-0.69, for the highest versus the lowest school-class level) and the ability to tan (OR 0.40; 95% CI 0.36-0.43). CONCLUSION: these findings confirmed that the fairness phenotype is associated with other skin cancer risk factors in children and pointed out that the high-risk phenotype has a geographical distribution consistent with the pattern of melanoma incidence in the Italian areas covered by the study.