Health related quality of life (HrQoL), is "the patient's subjective perception of the impact of his disease and its treatment on his daily life, physical, psychological and social functioning and well-being" and thus constitutes a patient reported outcome (PRO) of utmost importance. Generic HrQoL instruments can by definition not capture disease-specific parameters nor are they sensitive enough to detect their changes. In this study, a disease-specific HrQoL questionnaire for children and adolescents will be developed. Patients and parents will be involved in focus groups and interviews to identify relevant contents. The instrument will be tested for validity and reliability.

Inclusion Criteria:

• Patients with PD from age 8 years

  • Parent of patient(s) < 18 years with PD
  • Able to give informed consent as documented by signature
  • Sufficient command of the German language

Exclusion Criteria:

• - Inability to follow the procedures of the study, e.g. due to language problems or severely reduced health status