title: Short questionnaire for Parkinson's disease as a screening instrument.
abstract: OBJECTIVE
  To validate and simplify a screening questionnaire for the determination of PD.
  
  
  METHODS
  The screening questionnaire for PD was developed with the permission of the author. Reliability of the questionnaire was tested. To validate the questionnaire, 40 patients with PD and 93 controls completed the questionnaire. Multiple logistic regression analysis was used to determine the questions independently associated with PD and a risk score was calculated. The predictive performance of the risk score was evaluated via the area under the curve (AUC) of a receiver operating characteristics (ROC) curve.
  
  
  RESULTS
  The questionnaire showed a Cronbach's alpha coefficient of 0.73 with no difference between the initial and follow up scores. The mean content validity was 0.86. Of the 11 questions, 4 were independently associated with PD and were used to calculate the risk score. The scores of these questions were 2 (clumsiness)+4 (tremor)+2 (masked face)+2 (loss of balance while turning). The AUC of a ROC curve for the sum of risk score was 0.95. With a cutoff score of 5 or higher, the sensitivity and specificity were 0.88 and 0.95, respectively.
  
  
  CONCLUSIONS
  The screening questionnaire for PD is a reliable and valid instrument. The predictive performance of the simplified questionnaire is as good as the original.
authors.affiliation: Division of Neurology, Department of Medicine, Songklanagarind Hospital, Faculty of Medicine, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand. ssuwanna@medicine.psu.ac.th
authors.forename: Suwanna
authors.initials: S
authors.lastname: Setthawatcharawanich
authors.forename: Pornchai
authors.initials: P
authors.lastname: Sathirapanya
authors.forename: Kanitpong
authors.initials: K
authors.lastname: Phabphal
authors.forename: Kitti
authors.initials: K
authors.lastname: Limapichat
mesh_terms: D000368:Aged; D019540:Area Under Curve; D005260:Female; D006801:Humans; D018476:Hypokinesia / Q000175:diagnosis / Q000209:etiology; D007802:Language; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009127:Muscle Rigidity / Q000175:diagnosis / Q000209:etiology; D010300:Parkinson Disease / Q000150:complications / Q000175:diagnosis*; D012372:ROC Curve; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires; D013785:Thailand; D014202:Tremor / Q000175:diagnosis / Q000209:etiology