Reply: In practice, the delayed treatment approach may be implemented in 2 ways, either by instructing the parent to return for antibiotic treatment if symptoms persist or by providing the parent with a prescription for an antibiotic to be filled if the child has not shown improvement within a specified time (safety-net prescription).1,2 In Israel, the latter method is more frequently practiced. Since we would have been unable to differentiate between “safety-net prescriptions” and those which were intended for immediate purchase, measuring medications prescribed at the initial visit would have resulted in an overestimate of the true rate of antibiotic treatment for acute otitis media. Furthermore, we were most interested in estimating the impact of delayed treatment on antibiotic utilization associated with otitis media. As a result, we chose to focus on purchases, assuming that in most cases this would be a better measure of true consumption. With respect to “diagnostic transfers,” in our HMO, the dissemination of new treatment guidelines was not accompanied by active monitoring of physician practice patterns; thus, it is unlikely that physicians would have felt pressure to alter their diagnostic practices to justify antibiotic therapy. Furthermore, as can be seen in Figure 1, the first observed drop in otitis media incidence in children 0.5 to 2 years of age preceded the publication of the treatment guidelines in 2004.FIGURE 1.: Graph showing difference in FLACC score between each method for each child (For ease of interpretation the patients have been sorted in order of score and a new ID assigned).Finally, the dissemination of delayed treatment guidelines is just one example of initiatives that have been introduced in Israel and worldwide to reduce inappropriate antibiotic use, particularly for upper respiratory infections.3 We observed a drop in antibiotic purchases associated with acute otitis media that was temporally related to the implementation of the delayed treatment guidelines. It is entirely possible that concurrent interventions, as well as systemic changes in attitudes toward antibiotic utilization that these interventions reflect, may have contributed to our findings. We will continue to follow trends in diagnosis and purchasing within our HMO to verify that the observed changes persist with time. Zachi Grossman, MD Barbara S. Silverman, MD, MPH Maccabi Health Services Tel Aviv, Israel Dan Miron, MD Haemek Medical Center Afulah, Israel