title: Validation of the "QUICK" questionnaire--a tool for diagnosis of "wearing-off" in patients with Parkinson's disease.
abstract: The main objective of the present study was to test the validity of a 19-items instrument (QUICK Questionnaire, QQ) as a tool for screening of WO. Two hundred twenty-two patients (36.0% without WO; 64.0% with mild or moderate/severe WO) were included. Diagnosis of WO by the participant neurologist was considered the "gold standard." The complete Unified Parkinson's Disease Rating Scale battery, the Cumulative Illness Rating Scale-Geriatrics, and a form about WO presence and severity were completed by the neurologist. Patients independently completed the QQ just before the clinical assessment. As a whole, patients with WO were more disabled than patients without and patients with moderate/severe WO were in worse condition than patients with mild WO. The number of QQ symptoms declared to improve usually after the following dose of medication was 1.0 +/- 1.8 in the group without WO, but 6.0 +/- 3.8 in patients with WO (P < 0.001). A two QQ positive symptoms cut-off showed the following attributes: sensitivity, 88%; specificity, 80%; positive predictive value, 88.7%; negative predictive value, 79%; diagnostic accuracy, 85%; positive and negative likelihood ratios 4.4 and 0.15, respectively. The area under the ROC curve resulted 0.90 (CI95%: 0.86-0.94%). In summary, the QQ proved to be a valid screening tool to identify WO in PD patients. To our knowledge, the QQ is the only validated tool for diagnosis of WO.
authors.affiliation: Neuroepidemiology Unit, National Centre for Epidemiology, Carlos III, Institute of Health, Madrid, Spain. pmartinez@isciii.es
authors.forename: Pablo
authors.initials: P
authors.lastname: Martinez-Martin
authors.forename: Eduardo
authors.initials: E
authors.lastname: Tolosa
authors.forename: Basilio
authors.initials: B
authors.lastname: Hernandez
authors.forename: Xavier
authors.initials: X
authors.lastname: Badia
mesh_terms: D000328:Adult; D000368:Aged; D000978:Antiparkinson Agents / Q000627:therapeutic use*; D001007:Anxiety; D003430:Cross-Sectional Studies; D004522:Educational Status; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000175:diagnosis* / Q000188:drug therapy / Q000503:physiopathology* / Q000523:psychology; D011569:Psychiatric Status Rating Scales; D011594:Psychometrics; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D013064:Speech Disorders / Q000209:etiology; D011795:Surveys and Questionnaires
chemical_list: D000978:Antiparkinson Agents