Population-based Norwegian birth-cohort study (n=2,721 children), examined for egg allergy at a mean age of 2.5 years using parental report cross-checked against objective diagnostics (skin-prick testing, oral food challenge in a subset). Point prevalence of confirmed egg allergy at 2.5 years was 1.6% (95% CI 1.3-2.0%), with an estimated upper-bound cumulative incidence by that age of ~2.6%; roughly two-thirds of parent-reported cases were confirmed by objective testing, i.e. parental report alone substantially over-estimates true prevalence.
relevance_note: A directly-measured (not survey/self-report-only) population prevalence figure for egg allergy in young children — the base-rate harm data point the early-introduction RCTs (PETIT, STAR, EAT) are trying to move.
Methodology
Population-based Norwegian birth cohort (n=2,721). Parents completed questionnaires on any food reaction at 12, 18, and 24 months. Children with parent-reported egg reactions at age 2 were selected for a stepwise diagnostic work-up: home diet trials, skin-prick testing, and open plus double-blind placebo-controlled food challenges. Mean age at examination 2.5 years. A sample of children without perceived reactions was also assessed to estimate unrecognized reactions. Prevalence was corrected for the confirmation rate of parent report.
Results
O-22 - Confirmed egg-allergy prevalence 1.6% at age 2.5 years in a Norwegian birth cohort (cumulative incidence ~2.6%)
A directly-measured base-rate for egg allergy in toddlers, confirmed via a stepwise diagnostic procedure (home diet trials, skin-prick testing, open and double-blind placebo-controlled food challenges) rather than self-report alone.
Link to originalMethodology
Population-based Norwegian birth cohort (n=2,721). Parents completed questionnaires on any food reaction at 12, 18, and 24 months. Children with parent-reported egg reactions at age 2 were selected for a stepwise diagnostic work-up: home diet trials, skin-prick testing, and open plus double-blind placebo-controlled food challenges. Mean age at examination 2.5 years. A sample of children without perceived reactions was also assessed to estimate unrecognized reactions. Prevalence was corrected for the confirmation rate of parent report.
Link to original
O-23 - Parent-reported egg reactions confirmed ~two-thirds of the time; PPV rises from 50% to 100% with repeated reporting
Quantifies the gap between perceived and confirmed food reactions in young children: a measurement of self/parent-report validity for food allergy.
Link to original