Evaluating the prevalence of olfactory dysfunction in a pediatric population

Although smell loss has several potential etiologies (e.g., head trauma, allergic rhinitis, and enlarged adenoids) that are common among children, studies evaluating the prevalence of olfactory dysfunction in the pediatric population are rare. Several challenges confront the clinician or researcher hoping to evaluate odor identification ability in young children. Children are likely to be unfamiliar with many of the odor stimuli used in adult tests and have limited ability to read and identify labels to select from alternative choices, which is the typical adult response option. Consequently, specialized forms of olfactory tests must be developed for this population. Based on the format of the San Diego Odor Identification Test(1) and the delivery system of the Brief Smell Identification Test,(2) we are developing a short form odor identification test utilizing standardized odor stimuli in which participants match 6 odorants to pictures of the odor source. The pilot version of this test is being administered to children between the ages of 3-17 as part of the pre-surgical intake evaluation at the A.I. duPont Hospital for Children and as part of basic research studies at the Monell Center. The hospital study population is broad and includes children undergoing ear, nose, and throat surgery as well as controls subjects (children undergoing general surgery), with approximately 50 children per week eligible for evaluation. To improve correct interpretation of the results, stimulus familiarity is evaluated by having the child's parent/guardian also complete the test and answer a short questionnaire about the child's experience with the various odor stimuli. The challenges confronted in studying this clinical population as well as extrapolation to larger populations will be discussed.