Table 1. Demographic and clinical data relating to eczema and dry skin cases and population controls.

Demographic and clinical features	South African atopic eczema cases	Irish atopic eczema cases	Irish population controls	Scottish dry skin cases	Scottish population controls
Total number (% male)	102 (51.0)	442 (63.6)	460 (30.7)	178 (34.8)	100 (50.0)
Age in years mean (SD) and range	8.9 (9.9) 0.7 to 50.9	3.3 (11.8) 0.25 to 17.0	35.4 (9.2) 19 to 69	45.5 (48.1) 18 to 86	≥18
Eczema severity score, mean (SD) and range	10.4 (2.7) 5 to 15	11.3 (6.4) 3 to 15	0	NA	NA
Reported childhood eczema (%)	NA	NA	NA	16.3	NA

All patient studies conformed to the Declaration of Helsinki Principles and written informed consent was obtained. Irish population controls represent healthy adults from the population-based Trinity Biobank control samples; Scottish population controls are derived from adults attending hospital for haematologic investigations; eczema severity is scored using the Nottingham Eczema Severity Score (Emerson et al., 2000); dry skin was defined using a previously reported scoring system (Sergeant et al., 2009) and corresponds to visible fine scale (noted by a trained observer) on one/more body sites, self-reported use of a moisturizer more than once weekly or self-reported dry skin ‘moderately’ to ‘a lot’. SD, standard deviation; NA, not applicable.