In reply
We thank Bischoff, Crockett, and Schermer for their interest in our article, their insightful comments, and the opportunity to respond to them. They have correctly pointed out that the sex-stratified prevalence trends in Figure 1 of our article1 have been mislabeled. The male and female labels in the legend have been switched. The data from Ontario, Canada, which is depicted correctly in Table 1 of our article and in the text, agrees with the prevalence trends they described in the Netherlands—specifically, a consistently higher prevalence of COPD in men but also a trend showing that the prevalence in women is catching up with men.2 We thank them for pointing out this error. We have informed the Archives, and a correction was published in the June 28, 2010, issue.