Atopic dermatitis assessment
Parents were routinely encouraged to report skin concerns to the study
team. Suspected cases of AD were reviewed by the blinded investigator at
the earliest opportunity. Cases of AD <6 months were diagnosed
based on the presence of AD, assessed either in person or via
photographs when an in-person assessment was not possible. The UK
Working Party Diagnostic Criteria (UKWPDC) were applied when diagnosing
AD between 6 and 12 months 21. AD extent and severity
were evaluated (blinded) using SCORing Atopic Dermatitis (SCORAD) for
infants ≥6 months 22. During the high-level COVID‑19
restrictions, AD assessments, including SCORADs, were completed remotely
by the blinded investigator using photographs and video links (see
supplementary data for impact of COVID-19 on study). AD cases were
treated with a standardized treatment program which included advice on
emollient use and a topical steroid treatment, where required.