METHODS
atopy, allergy, Atopic Dermatitis, eczema
ATOPY, PEANUT ALLERGY, ATOPIC DERMATITIS, FOOD ALLERGY, ALLERGY, SECONDARY, ECZEMA
Study‐specific methods for the LEAP and EAT studies are published in full elsewhere and cohort demographics are summarized in Table The European Union‐funded iFAAM (Integrated Food Allergy and Allergen Management) project included a pooled analysis of individual‐level data from the RCTs of early allergenic food introduction. This pooled analysis allows estimates of oral tolerance induction among a number of different risk strata. Pooled estimates are adjusted for study‐specific and individual‐specific factors. Pooling the data across studies provides a robust and powerful estimate of the effect of oral tolerance induction. Analysis of the individual participant data enables estimates to be derived for the effect of early introduction of allergenic foods across the different ethnicities, baseline eczema severities and baseline IgE sensitization, a notable advantage in comparison with a meta‐analysis approach of summarized results.Detailed methods and levels of adherence for the LEAP and EAT studies have been reported elsewhere. Data collected in each study included allergy, sensitization and anthropometric endpoints, as well as demographics and family history of atopy. The challenges of harmonizing data from studies that have differences in design and methodology were extensively discussed, and agreement was reached on what could feasibly be analyzed in one dataset and a statistical analysis plan outlined. Using the iFAAM‐funded Allerg‐e‐lab, each data point was annotated with descriptors, and individual datasets from each study were then recoded, renamed and relabelled using the agreed upon matched variables, thus creating individual study datasets containing identical names, formats, labels and coding values. The harmonized datasets were merged together as a final integrated dataset and analyzed using methods described below.The outcomes evaluated were the point prevalence of peanut allergy by 3 years (EAT study primary endpoint) and by 5 years of age (LEAP study primary endpoint) and sensitization to peanut (measured as skin prick test [SPT] ≥1 mm or specific IgE ≥0.1 kU/L). Secondary outcome of baseline eczema, defined by objective Scoring Atopic Dermatitis (SCORAD) measurement, was also available from both studies.The integrated dataset was validated to ensure published study results on primary and secondary outcomes from the individual trials could be replicated. All published data on peanut allergy and sensitization were replicated in the integrated dataset before combined analyses began.