Inclusion Criteria:  Patients;  6-18 years old Diagnosed with primary ciliary dyskinesia Stability of clinical condition  Healthy controls;  6-18 years old  Exclusion Criteria:  Patients;  Diagnosed neurological, cognitive problem that can affect evaluations, Acute pneumonia or any infection History of exacerbation in the last 1 month More than 10% change in FEV1 in the last 6 months History of coronavirus disease (COVID-19) History of smoking Diagnosed vision, hearing, vestibular, or neurological problems that can affect balance Diagnosed orthopedic problems affecting mobility or a history of musculoskeletal surgery  Healthy controls;  Diagnosed neurological, cognitive problem that can affect evaluations Diagnosed vision, hearing, vestibular, or neurological problems that can affect balance History of coronavirus disease (COVID-19) History of smoking Trouble understanding and following the exercise test instruction