Hand eczema in a prospectively-followed cohort of office-workers.

A cohort of initially 111 office apprentices was prospectively followed for the duration of their training (2 and 3 years, respectively). The point prevalence of (slight) irritant or atopic hand eczema was 18.9% in the initial and 25.0% in the final examinations. Altogether, 37 cases of (slight) hand eczema were noted within the study period; of these, 10 qualified for a more conservative definition of "hand eczema". Expressed in a person-time-model, the incidence rates were 18.4 and 4.1 cases per 100 persons per year, respectively. The only significant risk factor for the development of (slight) irritant or atopic hand eczema within the study period was previous hand eczema--partly as a child, partly during a preceding occupation (e.g. hairdressing). Compared to one retrospective study in a cohort of older office employees and to a study sampling the general population, incidence rates were slightly higher in this study. Such differences may partly be due to different definitions of what has to be considered "a case of hand eczema". The necessity to (i) communicate on the method of case definition and (ii) develop guidelines for case definition in epidemiological studies is emphasised.