ArticleNeurology2021
Olfactory Testing in Parkinson Disease and REM Behavior Disorder: A Machine Learning Approach.
Article in Neurology, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 13 papers, 1 of them a synthesis that pooled it.
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Who cites it
13 citing papers in PubMed, 1 synthesis or guideline pooled it, 18 citations in OpenAlex.
- Olfactory dysfunction in aging and neurodegenerative diseases.Ageing research reviews · 2021Pooled it
- Machine learning-based brain magnetic resonance imaging radiomics for identifying rapid eye movement sleep behavior disorder in Parkinson's disease patients.BMC medical imaging · 2025Article
- Polygenic Risk Score Combined with Transcranial Sonography Refines Parkinson's Disease Risk Prediction.Movement disorders clinical practice · 2025Article
- Development of a simplified smell test to identify Parkinson's disease using multiple cohorts, machine learning and item response theory.NPJ Parkinson's disease · 2025Article
- Olfactory Dysfunction and Long-Term Trajectories of Sleep Disorders among early Parkinson's Disease: Findings from a Longitudinal Cohort.Neuroepidemiology · 2025Article
- A novel function for α-synuclein as a regulator of NCK2 in olfactory bulb: implications for its role in olfaction.Cell & bioscience · 2024Article
- Opportunities and Pitfalls of REM Sleep Behavior Disorder and Olfactory Dysfunction as Early Markers in Parkinson's Disease.Journal of Parkinson's disease · 2024Review
- Dopaminergic neurodegeneration in the substantia nigra is associated with olfactory dysfunction in mice models of Parkinson's disease.Cell death discovery · 2023Article
- Screening performances of an 8-item UPSIT Italian version in the diagnosis of Parkinson's disease.Neurological sciences : official journal of the Italian Neurological Society and of the Italian Society of Clinical Neurophysiology · 2023Article
- Article
- Food Neophobia, Odor and Taste Sensitivity, and Overall Flavor Perception in Food.Foods (Basel, Switzerland) · 2021Article
- Assessing Parkinson's Disease at Scale Using Telephone-Recorded Speech: Insights from the Parkinson's Voice Initiative.Diagnostics (Basel, Switzerland) · 2021Article
- Comparison between four published definitions of hyposmia in Parkinson's disease.Brain and behavior · 2021Article
Corrections and comments
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Authors and funding
12 authors at 1 institution in 1 country.
Funding
Abstract
objectiveWe sought to identify an abbreviated test of impaired olfaction amenable for use in busy clinical environments in prodromal (isolated REM sleep behavior disorder [iRBD]) and manifest Parkinson disease (PD).
methodsEight hundred ninety individuals with PD and 313 controls in the Discovery cohort study underwent Sniffin' Stick odor identification assessment. Random forests were initially trained to distinguish individuals with poor (functional anosmia/hyposmia) and good (normosmia/super-smeller) smell ability using all 16 Sniffin' Sticks. Models were retrained using the top 3 sticks ranked by order of predictor importance. One randomly selected 3-stick model was tested in a second independent PD dataset (n = 452) and in 2 iRBD datasets (Discovery n = 241, Marburg n = 37) before being compared to previously described abbreviated Sniffin' Stick combinations.
resultsIn differentiating poor from good smell ability, the overall area under the curve (AUC) value associated with the top 3 sticks (anise/licorice/banana) was 0.95 in the Development dataset (sensitivity 90%, specificity 92%, positive predictive value 92%, negative predictive value 90%). Internal and external validation confirmed AUCs ≥0.90. The combination of the 3-stick model determined poor smell, and an RBD screening questionnaire score of ≥5 separated those with iRBD from controls with a sensitivity, specificity, positive predictive value, and negative predictive value of 65%, 100%, 100%, and 30%.
conclusionsOur 3-Sniffin'-Stick model holds potential utility as a brief screening test in the stratification of individuals with PD and iRBD according to olfactory dysfunction. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that a 3-Sniffin'-Stick model distinguishes individuals with poor and good smell ability and can be used to screen for individuals with iRBD.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.