The aim of our study is to investigate the validity and reliability of the Dual Task Impact on Daily-living Activities (DIDA-Q) to assess the degree of difficulty felt when performing dual tasks during activities of daily living in patients with Parkinson's disease. In our study, the validity and reliability of a questionnaire to assess the degree of difficulty felt while performing dual tasks during activities of daily living in Parkinson's Disease will be examined for the first time. The study will include 95 participants with Hoehn-Yahr Stage 1-3, diagnosed with Idiopathic Parkinson's Disease and able to walk 10 metres without an assistive device.

Dual task ability is defined as the ability to perform two activities simultaneously . It is known that the ability to perform a motor or cognitive secondary activity at the same time during walking (talking to a person next to you while walking or carrying objects while walking) leads to gait and balance problems of different severity depending on the type of secondary task in Parkinson's Disease (PD). When patients with Parkinson's Disease (pwPD) are exposed to dual-task walking, their walking speed and length of stride decrease, and the frequency of freezing phenomena during walking increases. Consequently the risk of falling increase during activities of daily living. Individuals often perform dual tasks while performing activities of daily living because of the nature of the tasks' requirements. Therefore, it has become important to evaluate dual task performance in order to create the right treatment plan in the field of neurological physiotherapy and rehabilitation. Although dual task performance is evaluated with different formulae in the literature, the number of scales evaluating the level of difficulty perceived by the patient during the performance of activities of daily living under dual task is limited. The validity of the existing scales for PD has not been studied. The Dual-task Impact on Daily-living Activities Questionnaire (DIDA-Q) is a patient-reported questionnaire developed to assess the degree of difficulty perceived when performing dual tasks during activities of daily living.

Inclusion Criteria:

• Diagnosed with Idiopathic Parkinson's Disease according to UK Brain Bank criteria
• Walking at least 10 metres without an assistive device
• To have the cognitive capability to understand and answer the questions asked in the scale

Exclusion Criteria:

• Having any neurological disease other than idiopathic Parkinson's Disease
• The person has an orthopaedic or cardiopulmonary disease that affects walking
• Severe hearing-visual impairment

Patients who diagnosed with Parkinson's disease were included.