Evaluation of a screening questionnaire for Parkinson's disease in a Chinese population

A questionnaire designed to detect Parkinson's disease (PD) was developed by Tanner et al. in 1990. It consists of nine symptom questions and has been tested in several languages. We investigated the validity of the questionnaire in a Chinese population. Because handwriting is not common for elderly Chinese people, item 2 about "smaller handwriting" may be of no use, thus we also computed the performance of the questionnaire without item 2. The questionnaire was administered face-to-face to all 59 PD patients registered in our hospital and 217 non-neurological outpatients from the same hospital. All 217 outpatients were offered a short interview and examination related to PD. Of the 59 PD patients, 47 participated the study. None of the 217 non-neurological outpatients was diagnosed with parkinsonism. A combination of any three questions yielded the best balance between sensitivity (93.6%) and specificity (88.9%). There was no difference in validity between the questionnaire with and without item 2. This symptom questionnaire is an appropriate instrument to identify PD in a Chinese population. The questionnaire without item 2 is also satisfactory as a screening instrument to detect PD and may be more suitable for areas with a high illiteracy rate.