California Cancer Reporting System Standards Volume I: Abstracting and Coding Procedures
Follow-up information must be based on documentation of contact with the patient in one of the following forms:
Direct response to a letter or phone call to the patient or other contact person
A report by the patient's physician
Re-admission to the facility as an inpatient or outpatient
Death certificate
It might be necessary to trace the patient through such agencies and organizations as the registrar of voters, welfare agencies, labor unions, religious groups, or the Office of the State Registrar for a death certificate.