Introduction
The sense of smell, often underappreciated until it is compromised, plays a critical role in human health, safety, and psychological well-being. Olfactory dysfunction (OD) is more than a mere inconvenience; it is a clinical marker often associated with neurodegenerative diseases, post-viral syndromes, and significant reductions in quality of life. In the clinical landscape of Israel, where Hebrew is the primary language of medical interaction, the lack of a culturally and linguistically validated olfactory assessment tool has long been a hurdle for otorhinolaryngologists and neurologists. A recent study by Peled et al., published in the European Archives of Oto-Rhino-Laryngology, addresses this gap by validating the Hebrew version of the ‘Sniffin’ Sticks’ identification test (He-I).
The Burden of Olfactory Dysfunction
Olfactory dysfunction affects approximately 20% of the general population, with the prevalence increasing significantly in older demographics. The impact of OD spans multiple domains: nutritional intake is often compromised due to the loss of flavor perception, emotional well-being suffers as odors are tied to memory and social bonding, and safety risks escalate when individuals cannot detect gas leaks or spoiled food. In the wake of the COVID-19 pandemic, the clinical focus on olfaction has intensified, highlighting the need for standardized, psychophysical testing that transcends subjective patient self-reports.
Methodological Framework: The ‘Sniffin’ Sticks’ Test
The ‘Sniffin’ Sticks’ test is a globally recognized psychophysical method that utilizes felt-tip pens filled with odorants. The full battery evaluates three distinct components of olfaction: threshold (the lowest concentration of an odor a person can detect), discrimination (the ability to distinguish between different smells), and identification (the ability to name a specific scent from a list). While the threshold and discrimination components are largely independent of language, the identification component is highly dependent on cultural familiarity and linguistic accuracy. To adapt this for the Hebrew-speaking population, the researchers employed a rigorous forward-backward translation process to ensure that the descriptors provided in the multiple-choice identification task were both accurate and culturally recognizable.
Study Design and Participant Cohort
The cross-sectional study conducted in an Israeli cohort included 121 participants. This group was divided into 76 patients with diagnosed olfactory dysfunction and 45 healthy controls. To ensure a comprehensive validation, the participants underwent a battery of tests, including:
1. The Hebrew Sniffin’ Sticks Identification Test (He-I)
The primary focus of the study, assessing the participants’ ability to identify 16 common odors.
2. The Full TDI Battery
The gold-standard assessment combining Threshold, Discrimination, and Identification scores to provide a holistic view of olfactory performance.
3. The University of Pennsylvania Smell Identification Test (UPSIT)
A widely used ‘scratch-and-sniff’ test served as a secondary comparator to validate the Hebrew adaptation against an established international standard.
4. Subjective Measures
Participants provided a Visual Analog Scale (VAS) score to rate their own perception of their olfactory function, allowing researchers to compare objective findings with subjective experience.
Key Findings and Statistical Validation
The results of the study provide robust evidence for the clinical utility of the He-I test. The researchers reported a strong correlation between the He-I score and the full TDI battery (r = 0.93), suggesting that the identification component alone is an excellent surrogate for overall olfactory health. Furthermore, the correlation with the UPSIT (r = 0.86) confirms that the Hebrew adaptation maintains the diagnostic integrity of the original ‘Sniffin’ Sticks’ methodology.
Diagnostic performance was evaluated using Receiver Operating Characteristic (ROC) analysis. The Area Under the Curve (AUC) was calculated at 0.881, indicating high diagnostic accuracy. At a designated cut-off score of 10.5, the He-I test demonstrated a sensitivity of 93.3% and a specificity of 70.6%. This high sensitivity is particularly valuable for screening purposes, ensuring that the vast majority of patients with true olfactory deficits are correctly identified.
Internal consistency, measured by Cronbach’s alpha, reached 0.86, which is considered excellent for a diagnostic tool. Interestingly, the study also found a moderate correlation (r = -0.62) between subjective VAS scores and objective test results. This discrepancy underscores the necessity of psychophysical testing, as patients often inaccurately estimate the severity of their own olfactory loss.
Expert Commentary and Clinical Implications
The validation of the He-I test represents a significant advancement for Israeli medicine. By providing a tool that is specifically tailored to the linguistic and cultural nuances of the Hebrew-speaking population, clinicians can now offer more precise diagnoses and monitor treatment progress more effectively.
One of the strengths of this study is its use of a standardized translation protocol, which minimizes the risk of ‘lost-in-translation’ errors that can skew identification scores. However, it is important to note the study’s limitations, such as the relatively moderate specificity. This suggests that while the test is excellent at catching those with dysfunction, there may be some false positives among healthy individuals, perhaps due to cultural variations in scent familiarity that persist despite translation.
From a biological perspective, the identification task (I-score) is known to rely heavily on cognitive processing and semantic memory, which are localized in the orbitofrontal cortex and piriform cortex. Therefore, the He-I test serves not only as a measure of the peripheral olfactory system but also as a window into the central nervous system’s processing capabilities.
Conclusion
The Hebrew version of the ‘Sniffin’ Sticks’ identification test is a valid, reliable, and culturally appropriate instrument for assessing olfactory function in Israel. Its high sensitivity and strong correlation with established gold standards make it an indispensable tool for both clinical practice and academic research. As we move toward more personalized and culturally sensitive healthcare, such validations are essential for ensuring that diagnostic tools perform accurately across diverse global populations.
References
Peled I, Fischer T, Wasserman G, Hazan E, Herstain E, Abergel A, Carmel-Neiderman NN. Validation of the Hebrew version of the ‘Sniffin’ Sticks’ olfactory test: a cross-sectional study in an Israeli cohort. Eur Arch Otorhinolaryngol. 2025 Nov;282(11):5655-5664. doi: 10.1007/s00405-025-09627-y. Epub 2025 Oct 8. PMID: 41062839.
