Self-Administered Testing of Odor Threshold and Discrimination Using Sniffin’ Sticks—Reviving the “Odor-Curves-On-Paper” Method

Abstract

Introduction Olfactory testing helps in diagnosing olfactory dysfunction (OD). The Sniffin' Sticks odor test kit is widely used for research and can be reused and summed scores of threshold (T), discrimination (D), and identification (I) allow comparison to normative data. Testing can be time consuming and odor pens have to be presented by an examiner. The aim of this study was to investigate for a self-administration strategy for testing T and D. Methods Fifty healthy subjects (30 female, 20 male, mean age 27.3 years ± 8.1, range 18-58) were included. T was tested by an examiner (T-as) in a reversed staircase manner and self-tested with randomly presented concentrations (T-rand) and ascending methods of limits (T-aml). D testing was performed with assistance (D-as) and self-administered (D-s). For self-testing, examinees were instructed to perform the Bodor-curves-on-paper^method. Results Mean TDI was 35.9 ± 3.0, range 26.5-42.8. T-as scores were significantly lower than T-aml (p < 0.001) and T-rand (p < 0.05). T-aml was significantly faster than T-rand and T-as modalities (p < 0.001); Paired t test revealed no significant difference of D-as and D-s, in terms of scores and time needed (p > 0.05) and the mean difference was small (0.3). Conclusion The results of this study demonstrate the Bodor-curves-on-paper^method is applicable for D and with restrictions for T testing. Implications Self-administration of olfactory testing using Sniffin' Sticks can, with appropriate instructions, easily be performed and may improve patient care in personnel and (with limitations) time-restricted settings.

Ortho- and retronasal olfactory performance in rhinosurgical procedures: a longitudinal comparative study

“…Studies on this issue will be needed including objective tools like acoustic rhinometry. Not many clinics perform extended olfactory tests, although numerous tests are commercially available and also self-administration has been proposed for Sniffin' Sticks subtests saving personnel resources [37][38][39]. Retronasal tests have become more standardized, easy commercial accessibility, however, is still awaited [19,40,41].…”

Odor Mixtures in Identification Testing Using Sniffin’ Sticks: The SSomix Test

“…In summary, SSomix seemed to be a reliable, accurate, and short method requiring only the 16-item Sniffin' Sticks identification test to assess olfactory function in a novel approach to odor identification and could be used as a screening tool or in addition to shorter protocols. Similar to the SSomix test method, "Odor-Lines-On-Paper" have already been proposed for self-administered testing of all Sniffin' Sticks subtests 25,26 . Based on this method, clinicians may benefit from an additional test method using available tools thereby providing the possibility of self-administration.…”

“…We then grouped the hyposmic (n = 25) and anosmic (n = 12) cohorts together and defined a TDI of less than 30.75 (as previously described 28 ) so as to distinguish between normosmic (n = 51) and hyposmic/anosmic (n = 37) subjects for further analysis. Subjects in the normosmic group had an SSomix test score M ± SD (range) of 18.7 ± 3.7 (11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28), which was significantly higher compared to the hyposmic/anosmic group 11.8 ± 5.8 (3-23; t(56.1) = 6.4, p < 0.001). www.nature.com/scientificreports www.nature.com/scientificreports/…”

“…We chose the 16-item Sniffin' Sticks identification test to serve as the technical basis, since these 16 items are represented in the most widely used olfactory assessment tool in German-speaking countries and have been further adapted and validated for various other countries [33][34][35][36][37][38][39][40][41][42] . Regarding the procedure, we agreed on using the "Odor-Lines-On-Paper" method which has been validated for odor identification, discrimination, and threshold testing in previous studies of our working group 25,26 and has the potential for self-administration.…”

“…In the present work, we refined the German version of the 16-item Sniffin' Sticks identification test and evaluated a new screening test protocol to assess olfactory performance based on SSomix. It utilizes 13 mixtures of 11 odors (grouped into two or three) selected from the 16-item identification test, based on odor identification combined with a procedure using painted lines on a piece of paper ("Odor-Lines-On-Paper") 25,26 . The aim was to evaluate reproducibility and validate the SSomix test method in comparison to a benchmark test for olfactory performance.…”