China's Modified Version of Sniffin' Sticks 12-Identification Test Used in Chinese Parkinson's Disease and Multiple System Patients: Comparison of Three Olfactory Testing Methods.

Objectives: The aim of this study was to compare the Sniffin' Sticks 12-identification test (SIT-12), China-modified version of the SIT-12 test (Ch-SIT-12) and brief smell identification test for Chinese (B-SITC) in Chinese population of Parkinson's disease (PD) and multiple system atrophy (MSA).

Methods: 36 patients with PD and 7 patients with MSA were enrolled in this study. Three olfactory testing methods (SIT-12, Ch-SIT-12, and B-SITC) were used to test the olfactory function in all participants. Furthermore, demographic and clinical data were collected.

Results: There was no significant difference between three olfactory tests in patients with PD (B-SITC vs. SIT-12: =0.508; Ch-SIT-12 vs. B-SITC: =0.146; and SIT-12 vs. Ch-SIT-12: =0.375). Tremor-dominant (TD) subtypes have better olfactory function than akinetic-rigid dominant (ARD) subtypes when using Ch-SIT-12 (77.8% vs. 29.6%, =0.019) or B-SITC (55.6% vs. 14.8%, =0.026). There was a statistical difference between the PD and MSA using Ch-SIT-12 to test the olfactory function (=0.046).

Conclusions: Our results indicated that SIT-12, Ch-SIT-12 and B-SITC can be used for the detection of olfactory dysfunction in Chinese population of PD. TD subtypes may have better olfactory function than ARD subtypes. In addition, Ch-SIT-12 may be used to differentiate PD from MSA, but that should be confirmed in a larger population.