Mobile teledermatology is a valid method to estimate prevalence of melanocytic naevi in children.

The prevalence of melanocytic naevi in children correlates with sun exposure and may serve as an objective population risk indicator of future melanoma incidence. The aim was to investigate if mobile teledermatology could offer a valid methodology compared with standard manual, face-to-face counting of naevi on the back of children. Ninety-seven children aged 7-16 years were enrolled. One dermatologist performed manual naevi counting and imaging of the child's back using an iPhone 4S comprising a safe-coded mobile application. Two other dermatologists independently counted naevi from the images. Cohen's weighted kappa (κw) coefficient demonstrated substantial agreement for both dermatologists: κw = 0.69 (0.57-0.81 [95% confidence intervals]) and κw = 0.78 (0.70-0.86), compared with the manual assessment. Inter-rater reliability was also substantial (κw = 0.80 [0.73-0.87]). Use of mobile teledermatology proved valid for estimating naevi prevalence on the back and could provide a more feasible methodology following trends in sun exposure in children.