- A systematic review and meta-analysis looking at studies that included patients with olfactory dysfunction who had olfactory training. 10 studies with 639 patients were included in this review that met criteria.
- Olfactory dysfunction was due to multiple etiologies in these studies.
- Most studies used the Threshold, Discrimination and Identification (TDI) score as the primary endpoint with >5.5 or 6 considered significant improvement in most. Most studies did not separate etiology of smell loss.
- Patients who went through olfactory training had a statistically significant improvement in TDI score compared to control groups. Olfactory training in these studies showed improvement in discrimination and identification but not thresholds.
- There was a statistically significant difference in the olfactory training group compared to controls when looking at clinically significant improvement of TDI score (greater than 5.5 or 6 points based on the study).