Passive follow-up usually involves computerized searches of existing nonregistry files that may contain the cancer patient's name.

• A. Not applicable
• B. False
• C. Not sure
• D. True

Answer: (D)

The main idea here is how follow-up data are gathered in cancer studies: passive follow-up relies on existing records and automated data linkage rather than contacting patients directly. This statement is correct because passive follow-up uses computerized searches of nonregistry files—such as hospital records, vital statistics, death registries, or billing databases—to determine outcomes like survival. These sources may contain patient identifiers, including names, that enable matching and updating status without active patient or clinician contact. It’s an efficient approach for long-term outcomes, though it can be limited by data quality, incomplete records, or mismatches.