Olfactory screening of Parkinson's Disease patients and healthy subjects in China and Germany: A study of cross-cultural adaptation of the Sniffin' Sticks 12-identification test

Background Olfactory testing is a useful tool in the differential diagnosis of Parkinson's Disease (PD). Although fast and easy to use, the high intercultural variability of odor detection limits the world-wide use of the most common test sets. Objective The aim of this study was to test one of the most commonly used olfactory tests (Sniffin' Sticks 12-identification test) in an adapted version for a Chinese population of healthy subjects and PD patients. Methods For this purpose, cohorts of 39 Chinese and 41 German PD patients as well as 70 Chinese and 100 German healthy subjects have been examined both with the original and the adapted version of the Sniffin' Sticks test, the latter being designed according to the regional culture. Results The adapted Chinese version of the Sniffin' Sticks 12 identification test proved to discriminate Chinese PD patients from controls with a high specificity but relatively low sensitivity. Yet not all odor exchanges would have been necessary as the original odors including liquorice and coffee showed an equally high identification rate in the Chinese and German cohorts. Conclusions The results showed that the newly adapted test could be used as a screening test for PD related olfactory dysfunction in a Chinese population. However further investigation will be necessary to optimize the selection of odors for the Chinese version of the test