'Sniffin' Sticks': Olfactory Performance Assessed by the Combined Testing of Odor Identification, Odor Discrimination and Olfactory Threshold T. Hummel 14 , B. Sekinger 1 , S.R. Wolf 2 , E. Pauli 3 and G. Kobal 1 'Department of Experimental and Clinical Pharmacology and Toxicology, University of Erlangen-Numberg, KrankenhausstraSe 9, 91054 Erlangen, department of Oto-Rhino-Laryngology, University of Erlangen-Nurnberg, WaldstraBe 1, 91054 Erlangen, department of Neurology, University of Erlangen-Nurnberg, Schwabachanlage 6, 91054 Erlangen, Germany and 4 Smell and Taste Center, Department of Otorhinolaryngology, University of Pennsylvania, 3400 Spruce Street, Philadelphia, PA 19104, USA Correspondence to be sent to: Dr Thomas Hummel, Smell and Taste Center, Department of Otorhinolaryngology, University of Pennsylvania, 3400 Spruce Street, Philadelphia, PA 19104, USA Abstract 'Sniffin' Sticks' is a new test of nasal chemosensory performance based on pen-like odor dispensing devices. It comprises three tests of olfactory function, namely tests for odor threshold (n-butanol, testing by means of a single staircase), odor discrimination (16 pairs of odorants, triple forced choice) and odor identification (16 common odorants, multiple forced choice from four verbal items per test odorant). After extensive preliminary investigations the tests were applied to a group of 104 healthy volunteers (52 female, 52 male, mean age 49.5 years, range 18-84 years) in order to establish test-retest reliability and to compare them with an established measure of olfactory performance (the Connecticut Chemosensory Clinical Research Center Test, CCCRC). Performance decreased with increasing age of the subjects (P < 0.001). Coefficients of correlation between sessions 1 and 2 were 0.61 for thresholds, 0.54 for discrimination and 0.73 for identification. Butanol thresholds as obtained with the CCCRC increased as a function of age; this relation to the subjects' age was not found for the CCCRC odor identification task. The test-retest reliability for CCCRC thresholds was 0.36, for odor identification it was 0.60. It is concluded that 'Sniffin' Sticks' may be suited for the routine clinical assessment of olfactory performance. Chem Senses 22: 39-52, 1997. Introduction Tests for the assessment of olfactory function are numerous. Doty and Kobal, 1995). This situation very often reduces However, in the clinical practice of otorhinolaryngology or clinical testing of olfactory ability to the administration of neurology few, if any, of them are actually used. The one or two common odors (e.g. coffee or cloves) in reasons may be found in the inconsistency of some tests, the combination with the question whether the patient is able to lack of normative data, the time needed for administration identify the odor. The lack of an appropriate means for the and the limited availability of these tests (for review see testing of olfactory function limits the quality of medical © Oxford University Press by guest on July 13, 2011 chemse.oxfordjournals.org Downloaded from