Trial reportPloS one2013
Olfactory training in patients with Parkinson's disease.
Trial report in PloS one, 2013. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 62 papers, 4 of them syntheses that pooled it.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
62 citing papers in PubMed, 4 syntheses or guidelines pooled it, 154 citations in OpenAlex.
- The efficacy of olfactory training in improving olfactory function: a meta-analysis.European archives of oto-rhino-laryngology : official journal of the European Federation of Oto-Rhino-Laryngological Societies (EUFOS) : affiliated with the German Society for Oto-Rhino-Laryngology - Head and Neck Surgery · 2024Pooled it
- The Pitfalls and Perspectives of Assessing Olfactory Function via Optical Brain Imaging.Turkish archives of otorhinolaryngology · 2023Pooled it
- Systematic review and meta-analysis of Sniffin Sticks Test performance in Parkinson's disease patients in different countries.European archives of oto-rhino-laryngology : official journal of the European Federation of Oto-Rhino-Laryngological Societies (EUFOS) : affiliated with the German Society for Oto-Rhino-Laryngology - Head and Neck Surgery · 2022Pooled it
- Efficacy of olfactory training in patients with olfactory loss: a systematic review and meta-analysis.International forum of allergy & rhinology · 2016Pooled it
- Intra Nasal Use of Ethylene Diamine Tetra Acetic Acid for Improving Olfactory Dysfunction Post COVID-19.American journal of rhinology & allergy · 2023Trial
- Acupuncture is associated with a positive effect on odour discrimination in patients with postinfectious smell loss-a controlled prospective study.European archives of oto-rhino-laryngology : official journal of the European Federation of Oto-Rhino-Laryngological Societies (EUFOS) : affiliated with the German Society for Oto-Rhino-Laryngology - Head and Neck Surgery · 2022Trial
- Olfactory training with Aromastics: olfactory and cognitive effects.European archives of oto-rhino-laryngology : official journal of the European Federation of Oto-Rhino-Laryngological Societies (EUFOS) : affiliated with the German Society for Oto-Rhino-Laryngology - Head and Neck Surgery · 2022Trial
- Citronellal Alleviates Cognitive Impairment by Inhibiting NHE1-Mediated Mitochondrial Damage in Vascular Dementia.Applied biochemistry and biotechnology · 2026Article
- Age-related changes in olfactory function: electrophysiological recordings from the olfactory mucosa and human brain.npj aging · 2026Article
- Human olfactory sensitivity varies across geographical locations.Scientific reports · 2026Article
- Sudden sensorineural olfactory loss: a structured narrative review and proposal for a standardised terminological framework.Frontiers in surgery · 2026Review
- Prospective Randomized Controlled Trial of the Impact of Olfactory Training on Cognitive and Emotional Function in Individuals with Parkinson Disease.Archives of rehabilitation research and clinical translation · 2025Article
- The plasticity of olfactory learning in culinary students and matched controls.Brain imaging and behavior · 2025Article
- Is it Possible to Reuse the University of Pennsylvania Smell Identification Test (UPSITInternational archives of otorhinolaryngology · 2025Article
- [The diagnosis and treatment progress of olfaction disorders in chronic rhinosinusitis].Lin chuang er bi yan hou tou jing wai ke za zhi = Journal of clinical otorhinolaryngology head and neck surgery · 2025Review
- Discriminating Parkinson's disease patients from healthy controls using nasal respiratory airflow.Communications medicine · 2024Article
- Maximizing Participation in Olfactory Training in a Sample with Post-COVID-19 Olfactory Loss.Brain sciences · 2024Article
- The Role of the Stimulus in Olfactory Plasticity.Brain sciences · 2023Review
- Olfactory training with essential oils for patients with post-COVID-19 smell dysfunction: A case series.European journal of integrative medicine · 2023Article
- Olfactory Function and Olfactory Disorders.Laryngo- rhino- otologie · 2023Article
2 more citing papers are in PubMed but not listed here.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
8 authors at 2 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
objectiveDecrease of olfactory function in Parkinson's disease (PD) is a well-investigated fact. Studies indicate that pharmacological treatment of PD fails to restore olfactory function in PD patients. The aim of this investigation was whether patients with PD would benefit from "training" with odors in terms of an improvement of their general olfactory function. It has been hypothesized that olfactory training should produce both an improved sensitivity towards the odors used in the training process and an overall increase of olfactory function.
methodsWe recruited 70 subjects with PD and olfactory loss into this single-center, prospective, controlled non-blinded study. Thirty-five patients were assigned to the olfactory training group and 35 subjects to the control group (no training). Olfactory training was performed over a period of 12 weeks while patients exposed themselves twice daily to four odors (phenyl ethyl alcohol: rose, eucalyptol: eucalyptus, citronellal: lemon, and eugenol: cloves). Olfactory testing was performed before and after training using the "Sniffin' Sticks" (thresholds for phenyl ethyl alcohol, tests for odor discrimination, and odor identification) in addition to threshold tests for the odors used in the training process.
resultsCompared to baseline, trained PD patients experienced a significant increase in their olfactory function, which was observed for the Sniffin' Sticks test score and for thresholds for the odors used in the training process. Olfactory function was unchanged in PD patients who did not perform olfactory training.
conclusionThe present results indicate that olfactory training may increase olfactory sensitivity in PD patients.
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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.