We read with interest the article by Kraus et al1 regarding the hepatitis B immunization practices of Illinois pediatricians. There is significant interest nationwide in the degree to which pediatricians and family physicians have adopted universal hepatitis B immunization of infants. However, we are concerned that the sampling frame used by the authors of this study may overestimate agreement with and adoption of this recommendation.
The authors included only members of the Academy of Pediatrics (AAP) in their sampling frame. Although our initial studies in this area found no differences in recommendation adoption between members and nonmembers of the AAP,2 our subsequent work that assessed these elements over time demonstrated lower rates of agreement and adoption among nonmember pediatricians.3 It is likely that the increased awareness among AAP members found in our earlier studies influenced eventual rates of adoption.
Although the majority of pediatricians in the United