The purpose of this study was to investigate the reliability and validity of a self-reported questionnaire for estimating the prevalence of hand eczema and other hand dermatoses. All pupils in grades 1 and 3 from the secondary schools in Växjö, in southern Sweden, were invited to participate in the study, which consisted of two parts, a questionnaire and a clinical examination. Of those invited, 2572 (98.6%) responded to the questionnaire. Of the respondents, 2535 pupils (98.5%) were clinically examined. The kappa value for the questionnaire findings, compared with the diagnosis from the clinical examination, was 0.79, indicating good agreement. The sensitivity of the questionnaire findings was 73% (95% confidence interval [CI]: 0.6425-0.7975), and the specificity was 99% (95% confidence interval [CI]: 0.9860-0.9940). The self-reported questionnaire was suitable for detecting hand dermatosis in a population of secondary school children and may be used as a cost-effective and reliable method of investigating the prevalence of hand dermatosis in epidemiological studies.