To the Editor.
—The assertion by Dr Soll1 that "single-antibiotic combinations of either clarithromycin or amoxicillin with PPIs... efficacy is less than 70%" is incorrect. While appropriate for amoxicillin, this efficacy level is not valid for clarithromycin. The H pylori eradication rate of 83% for clarithromycin and omeprazole has been published.2 Clarithromycin plus omeprazole yielded consistent eradication rates of 74% or more in 3 of 4 well-controlled studies, which were the basis for FDA approval of this combination.3 These studies were randomized double-blind, multicenter studies with rigorous assessment of H pylori status and follow-up for 6 months posttreatment; they represent both US and European populations. In contrast, essentially all results presented in Figure 1 in the Consensus Statement by Dr Soll were from unblinded studies, mostly conducted in Europe.Differences in study design and assessment of H pylori eradication hamper comparisons among studies. The most effective regimen can only be