The purpose of this study is to provide validation of patient-reported data in the VCRC Patient Contact Registry by comparing patient-reported data with data provided by the physician who is the primary provider caring for the patient's vasculitis. Patients enrolled in the Patient Contact Registry with Behcet's disease, eosinophilic granulomatosis with polyangiitis (Churg-Strauss) (EGPA), giant cell arteritis (GCA), granulomatosis with polyangiitis (Wegener's) (GPA), microscopic polyangiitis (MPA), polyarteritis nodosa (PAN), and Takayasu's arteritis (TAK) were invited via email to participate in this study.

Via email, consent was obtained from at least 20 randomly selected patients with the seven forms of vasculitis detailed above in the VCRC Patient Contact Registry who have completed the Diagnostic Questionnaire. The form was sent in PDF format to the patient, who either printed out or emailed the form to his or her primary vasculitis provider to complete. This form included the same questions in the patient questionnaire, with minor reformatting and a few expanded details to verify the patient-provided data (please see appendix B). If the 20 questionnaires are not returned one month after the initial recruitment email to the Patient Contact Registry participants, 20 additional participants with the seven forms of vasculitis will be selected randomly and will be asked to participate in this study. The survey data is stored by the Rare Diseases Clinical Research Network's (RDCRN) Data Management and Coordinating Center (DMCC) at the University of South Florida. The data is de-identified. Names or other personal health information were not collected. Upon conclusion of the study period, the data will be sent to Dr. Kathleen McKinnon. All data collected will be sent to the database of Genotypes and Phenotypes (dbGaP) to be stored indefinitely.

Inclusion Criteria:

• At least 20 patients with each of the following self-identified diagnoses in the VCRC Patient Contact Registry: Behçet's disease, EGPA, GCA, GPA, MPA, PAN, and TAK who have completed the online questionnaires.

Exclusion Criteria:

• Inability to provide informed consent and complete survey
• Patients whose diagnosis of vasculitis was not confirmed by a physician
• Patients who did not complete the initial questionnaire in its entirety

Consent will be obtained from at least 20 randomly selected patients with each of the following self-identified diagnoses in the VCRC Patient Contact Registry: Behçet's disease, EGPA, GCA, GPA, MPA, PAN and TAK that have already completed the VCRC Diagnostic Questionnaires. Permission will be obtained to contact subjects' primary vasculitis care providers to request that the providers complete an online version of this questionnaire (or print copy, if they prefer), and request specific chart items from their office to further verify the data. The sensitivity and specificity for various combinations of the diagnostic questions to predict vasculitis and to confirm type of vasculitis will be calculated using physician diagnosis / chart review as the gold standard.