PDQ-39 Questionnaire
The PDQ-39 is the most widely used Parkinson’s Disease (PD) specific patient reported outcome measure. It was developed on the basis of interviews with people with Parkinson's Disease, and has been extensively validated, and translated into over eighty languages. An eight item shorter form is also available.
Further information on the measure (including the user manual), together with licensing details, can be found on the PDQ-39 page on the Oxford University Innovation website.