With great interest, we read the article by Lowe et al1 on the effect of pet ownership and exposure to indoor allergens on lung function at age 3 years. Disentangling the contributions of various sources to the development of allergy is complicated. In this study, exposure to indoor allergens was measured only once, at age 3 years, the same age at which lung function was measured.
van der Wouden JC, Bernsen RMD. Pet Ownership and Exposure to Indoor Allergens. Arch Pediatr Adolesc Med. 2005;159(4):400-401. doi:10.1001/archpedi.159.4.401-a