Performance on a smell screening test (the MODSIT): a study of 510 predominantly illiterate Chinese subjects.

The 12-item Modular Smell Identification Test (MODSIT) was administered to 239 male and 271 female Chinese subjects whose age ranged from 50 to 92 years (68.3 +/- 10.9) and whose education ranged from 0 to 20 years (2.5 +/- 4.3). Every participant was examined by a physician and was found to be free of dementia, stroke, and Parkinson's disease. Different from the standard procedures, only one-third of each odor pad was used for each subject, the four odor choices were presented orally for the majority of subjects, and they were not forced to make a selection when they could not detect or identify the odor. The average level of performance was 46% correct. The score was negatively associated with age, positively associated with education and with performance on a dementia screening test, and corroborated with subjects' report of smell deterioration in recent years. Nonsmokers and women performed better than smokers and men. The 12-item MODSIT had an internal consistency reliability of 0.73 and a 7-month retest stability of 0.57 with different examiners. The MODSIT is satisfactory for group studies, even when administered with suboptimal procedures such as those used in the present study.