Multi-center, retrospective observational cohort study in 4 tertiary referral centers in Cairo over the period from 2004 to 2016.

Study population. including all patients with idiopathic Parkinson disease attending. Patients were diagnosed in accordance to the United Kingdom - Parkinson Disease Society Brain Bank criteria.

Retrospective, observational study that involve Medical Record Review (MRR). Data extraction and collection from medical records was organized through an electronic structured data collection form by two of authors (H.S and N.S).

The abstraction documents included; patient's age, sex, family history, age at onset, type and side of motor symptoms onset, associated non-motor manifestations. Moreover; management plan, drug history, outcome and disease progression were also verified and recorded.

During medical record reviewing (MRR); any missing documentation or poorly recorded information was managed by deleting the case.

Inclusion Criteria:

• All patients with Parkinsonian syndromes

Exclusion Criteria:

• Records with missing operationalized variables from patient records

Parkinsonian syndromes