Olfactory threshold and odor discrimination ability in children – evaluation of a modified “Sniffin’ Sticks” test

Abstract

The clinical diagnostics of olfactory dysfunction in children turns out to be challenging due to low attention span, insufficient linguistic development and lack of odor experiences. Several smell tests have been developed for adults. Most of these examinations take a relatively long time and require a high level of concentration. Therefore, the aim of the current study was to evaluate an odor discrimination and olfactory threshold test using the frequently used “Sniffin’ Sticks” in children and adolescents in a simplified two-alternative-forced-choice version (2AFC) and compare it to the original three-alternative-forced-choice test (3AFC). One-hundred-twenty-one healthy participants aged between 5 and 17 years took part in this study. Within each of the two sessions participants underwent olfactory testing using the modified 2AFC as well as the standard 3AFC method. A better test-retest reliability was achieved using the original 3AFC method compared to the modified 2AFC. This was true for the odor discrimination as well as the olfactory threshold. Age had a significant influence on both tests, which should be considered when testing young children. We discuss these findings with relation to the existing norms and recommend using the 3AFC version due to a better test-retest reliability to measure olfactory function in children.

Updated Sniffin’ Sticks normative data based on an extended sample of 9139 subjects

“…Therefore, age-appropriate olfactory tests are necessary and have indeed been developed [9, 11, 22]. …”

Pediatric Barcelona Olfactory Test ̶ 6 (pBOT-6): Validation of a Combined Odor Identification and Threshold Screening Test in Healthy Spanish Children and Adolescents

“…This is in the same line with previous studies demonstrating age-related increases in children's IS [14,17,18,27]. However, in the current study,although we observed a tendency toward a better threshold score with age, differences did not reach statistical significance.A previous study evaluated olfactory threshold in children using a modified "Sniffin' Sticks" threshold test [20]. They reported an increase in threshold scores with age.…”

“…However, smell loss patients were initially evaluated with the Smell Wheel test [16], which has no normative/reference values published to date. Therefore the difference between partial or total loss of smell [13] and the "Sniffin' Sticks" olfactory threshold test [20] seem suitable and reliable for children and adolescents. However, these tests were developed in a specific country with country specific odors that may not be suitable for Spanish children.…”

“…However, this test does not include a threshold test to complement identification task for the assessment of sensorial dysfunction. A composite analysis of several components of olfaction, especially including assessment of odour thresholds, provides the most meaningful approach to human olfactory function [19,20].…”

Association Between Olfactory Performance and Affective Symptoms in Children

“…Therefore, we decided to only administer the odor discrimination test. Gellrich et al (2017) recently evaluated the discrimination task of the sniffin' stick test in a children sample (ages 5-17 years) and found sufficient retest reliability (r = 0.69).…”