The double-blind placebo, randomized controlled study by Cohen et al1 investigated the effectiveness of Chizukit (Hadas Corp Ltd, Yokneam, Israel), an herbal preparation of echinacea, propolis, and vitamin C, in preventing respiratory tract infection in children. This study enrolled 430 children, aged 1 to 5 years, from 10 primary care community clinics in Israel. Children were randomized to treatment or placebo groups and followed up for a 12-week period during the respiratory season. There were several primary outcomes, but the main outcomes studied were the number and duration of illness episodes. Children treated with Chizukit had a statistically significant reduction in the number and duration of illness episodes when compared with children treated with a placebo. We appraised the article for validity and generalizability using the Users' Guide to the Medical Literature articles about therapy or prevention