Validation and reproducibility of the International Study of Asthma and Allergies in Childhood (ISAAC) Written Atopic Eczema Questionnaire for telephone survey in children aged 6–7 years()

BACKGROUND: The prevalence of atopic eczema is unknown in many countries. The International Study of Asthma and Allergies in Childhood (ISAAC) is an epidemiological landmark in the study of allergic diseases. OBJECTIVE: To validate and assess the reproducibility of the ISAAC Written Atopic Eczema Questionnaire (WAEQ) for children aged between 6 and 7 years by telephone contact. METHODS: Observational study through interviews with guardians of children aged 6 to 7 years using the ISAAC atopic eczema module questionnaire in three different phases separated by 2 weeks: telephone interviews in the first and third contacts and in-person interviews under supervision in the second contact. Reproducibility was estimated using the Kappa index and validation using the sensitivity and specificity coefficients. RESULTS: Data from 88 children (32 from the atopic eczema group) were analyzed. Reproducibility showed almost perfect agreement for the questions “Recurrent pruritic lesions” and “Lesions in typical locations” (Kappa between 0.81–0.82), while a substantial agreement was observed for all other indicators (Kappa variation between 0.66 and 0.78). The validation showed high specificity (≥ 80.4%) and sensitivity (≥ 87.5%) for all questions, except those related to chronicity and medical diagnosis (34.4% and 40.6%, respectively). STUDY LIMITATIONS: Non-random selection, no sample size calculation, participants from a tertiary hospital and study period coincident with the Coronavirus pandemic. CONCLUSIONS: Our results showed that the ISAAC atopic eczema module questionnaire by telephone interviews has good reproducibility and high agreement with the clinical diagnosis of atopic eczema. It may be an appropriate alternative tool in epidemiological studies of childhood atopic eczema, especially in periods of social isolation.