The sensitivity and specificity of the 9-item Wearing-off Questionnaire

Parkinsonism Relat Disord. 2008;14(3):205-12. doi: 10.1016/j.parkreldis.2007.07.013. Epub 2007 Sep 27.


Objective: This multicenter, cross-sectional study was conducted to determine the sensitivity and specificity of a 9-item Wearing-off Questionnaire (WOQ-9) compared with assessment by a clinician.

Methods: Patients with a diagnosis of Parkinson's disease (PD) for 5 <or=years, and receiving stable antiparkinsonian therapy for >or=90 days, completed the WOQ-9 before independent evaluation by the physician.

Results: One hundred fifty-seven patients reported WO using the WOQ-9; only 79 had been previously diagnosed with WO by a physician. The most frequent items used by physicians to diagnose WO included type of symptoms (69.6%), symptom response (63.3%), and timing of symptom response (58.2%) to medication. Physician assessment of WO and WOQ-9 results corresponded in 76 of 79 cases; physicians disagreed with WO identification in 81 of 157 cases. Sensitivity of the WOQ-9 was 96.2% and specificity was 40.9%.

Conclusion: The WOQ-9 is a useful screening tool to aid diagnosis of WO in PD patients.

Publication types

  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Antiparkinson Agents / therapeutic use
  • Case-Control Studies
  • Cross-Sectional Studies
  • Disability Evaluation*
  • Drug Resistance / physiology*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Outcome Assessment, Health Care*
  • Parkinson Disease / drug therapy
  • Parkinson Disease / physiopathology*
  • Retrospective Studies
  • Sensitivity and Specificity
  • Severity of Illness Index
  • Surveys and Questionnaires*


  • Antiparkinson Agents