This Article  • Full text  • PDF  • Send to a friend  • Save in My Folder  • Save to citation manager  • Permissions  Citing Articles  • Contact me when this article is cited  Related Content  • Similar articles in this journal  Topic Collections  • Viral Infections  • Public Health, Other  • Statistics and Research Methods  • Alert me on articles by topic

	Since this article does not have an abstract, we have provided the first 150 words of the full text and any section headings.

We recently reviewed the provocative study by Thorson and colleagues¹ that documented an association between exposure to sick or dead birds and the occurrence of mild flulike illness in our introductory course in epidemiology. When preparing for this session, we noticed 2 issues that we would like to bring to the attention of the journal's readers. First, the exposure frequency distribution provided in Table 1 is nested.¹ That is, those persons exposed to "direct contact with sick or dead poultry" (n = 6702) are also included in the less severe exposure group "sick or dead poultry in household" (n = 11 755) and both of these groups are included in the exposure group "raise or keep poultry in household" (n = 38 373). We are concerned therefore, that the corresponding multivariate analysis may have been conducted on many more observations than numbers of persons in the study. This approach violates the independence assumption required. Second, the crude odds . . . [Full Text of this Article]

AUTHOR INFORMATION
Patti A. Groome, PhD; Harriet Richardson, PhD