Course: Development and Validation of a Novel At-home Smell Assessment
CME Credits: 1.00
Released: 2022-01-13
Key Points
Question Can an olfactory dysfunction be assessed via commonly available household items?Findings In this diagnostic study of 115 adults with self-reported olfactory dysfunction, 2 shorter, patient-reported assessments using common household items were easy to use and had high accuracy when detecting olfactory dysfunction.
Meaning These findings suggest that these novel assessments can be used by people seeking to test their sense of smell and by health care professionals to detect olfactory dysfunction.
Abstract
Importance Current tools for diagnosis of olfactory dysfunction (OD) are costly, time-consuming, and often require clinician administration.Objective To develop and validate a simple screening assessment for OD using common household items.
Design, Setting, and Participants This fully virtual diagnostic study included adults with self-reported OD from any cause throughout the US. Data were collected from December 2020 to April 2021 and analyzed from May 2021 to July 2021.
Main Outcomes and Measures Participants with self-reported olfactory dysfunction took a survey assessing smell perception of 45 household items and completed the Clinical Global Impression–Severity (CGI-S) smell questionnaire, the University of Pennsylvania Smell Identification Test (UPSIT), and the 36-item Short Form Survey (SF-36). Psychometric and clinimetric analyses were used to consolidate 45 household items into 2 short Novel Anosmia Screening at Leisure (NASAL) assessments, NASAL-7 (range, 0-14; lower score indicating greater anosmia) and NASAL-3 (range, 0-6; lower score indicating greater anosmia).
Results A total of 115 participants were included in the study, with a median (range) age of 42 (19-70) years, 92 (80%) women, and 97 (84%) White individuals. There was a moderate correlation between the UPSIT and NASAL-7 scores and NASAL-3 scores (NASAL-7: ??=-0.484; NASAL-3: ??=-0.404). Both NASAL-7 and NASAL-3 had moderate accuracy in identifying participants with anosmia as defined by UPSIT (NASAL-7 area under the receiver operating curve [AUC], 0.706; 95% CI, 0.551-0.862; NASAL-3 AUC, 0.658; 95% CI, 0.503-0.814). Scoring 7 or less on the NASAL-7 had 70% (95% CI, 48%-86%) sensitivity and 53% (95% CI, 43%-63%) specificity in discriminating participants with anosmia from participants without. Scoring 2 or less on the NASAL-3 had 57% (95% CI, 36%-76%) sensitivity and 78% (95% CI, 69%-85%) specificity in discriminating participants with anosmia from participants without. There was moderate agreement between UPSIT-defined OD categories and those defined by NASAL-7 (weighted ??=-0.496; 95% CI, 0.343-0.649) and those defined by NASAL-3 (weighted ??=-0.365; 95% CI, 0.187-0.543). The agreement with self-reported severity of olfactory dysfunction as measured by CGI-S and the NASAL-7 and NASAL-3 was moderate, with a weighted ? of 0.590 (95% CI, 0.474-0.707) for the NASAL-7 and 0.597 (95% CI, 0.481-0.712) for the NASAL-3.
Conclusion and Relevance The findings of this diagnostic study suggest that NASAL-7 and NASAL-3, inexpensive and brief patient-reported assessments, can be used to identify individuals with OD. As the burden of COVID-19–associated OD increases, these assessments may prove beneficial as screening and diagnostic tools. Future work will explore whether the NASAL assessments are sensitive to change and how much of a change is clinically important.
Educational Objective
To identify the key insights or developments described in this article
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