['Topical corticosteroids are the usual treatment for atopic dermatitis (AD) in children but can have side-effects.', 'This study compared the efficacy and safety of 0.03% tacrolimus ointment applied once or twice daily over a 3-week period with the twice daily application of 1% hydrocortisone acetate (HA) ointment in children with moderate to severe AD.', 'Patients applied ointment daily to all affected body surface areas. The primary study endpoint was the percentage change in the modified Eczema Area and Severity Index (mEASI) between baseline and treatment end.', 'Six hundred and twenty-four patients, aged 2-15 years, applied 0.03% tacrolimus ointment once daily (n = 207), twice daily (n = 210) or 1% HA twice daily (n = 207). By the end of treatment, application of 0.03% tacrolimus ointment both once or twice daily resulted in significantly greater median percentage decreases in mEASI (66.7% and 76.7%, respectively) compared with 1% HA (47.6%; P < 0.001). Furthermore, the median percentage decrease in mEASI was significantly greater for patients applying 0.03% tacrolimus twice daily compared with once daily (P = 0.007). Patients with severe AD benefited especially from twice daily application of 0.03% tacrolimus ointment compared with once daily application (P = 0.001). Transient mild to moderate skin burning occurred significantly more often in the 0.03% tacrolimus groups (P = 0.028) but resolved in most cases within 3-4 days. Laboratory parameters showed no clinically relevant changes.'] Is 0.03 % Tacrolimus ointment applied once or twice daily more efficacious than 1 % hydrocortisone acetate in children with moderate to severe atopic dermatitis : results of a randomized double-blind controlled trial?