Hoffman, L. (2009). Treating Childhood Anxiety. N Engl J Med 360:2475, June 4, 2009 Correspondence

To the Editor: In the editorial accompanying the report by Walkup et al., Emslie1 states, in support of randomized, controlled trials, “It appears unlikely that the majority of children with severe and persistent anxiety disorders are receiving optimal evidence-based care in the community.” I do not believe that the results reported by Walkup et al. can be generalized, in that 84% of potential subjects were excluded (3066 screened, and 488 randomly assigned to a study group), making the external validity2 of the findings doubtful.