Humidity in Treating Croup In a randomized controlled trial conducted with children suffering from viral croup, 46 children were treated with low humidity while 46 other children were treated with high humidity. Researchers used the Westley Croup Score to assess the results after one hour. The low-humidity group had a mean score of 0.98 with a standard deviation of 1.22, while the high-humidity group had a mean score of 1.09 with a standard deviation of 1.11 (based on data from “Controlled Delivery of High vs Low Humidity vs Mist Therapy for Croup Emergency Departments,” by Scolnik et al., Journal of the American Medical Association, Vol. 295, No. 11). Use a 0.05 significance level to test the claim that the two groups are from populations with the same standard deviation.