Which of these is NOT a method of record linkage?

The correct answer is manual entry because it does not represent a method of record linkage. Record linkage involves the process of identifying and connecting records that refer to the same entity across different databases or data sources. This typically relies on various automated or semi-automated methods to match and consolidate data effectively.

Casefinding is a proactive method used to identify new cases of cancer, ensuring that registries are comprehensive and current. Passive follow-up refers to the method of tracking patients after diagnosis through existing databases or other data sources without direct patient interaction. Duplicate detection focuses on identifying and removing duplicate records in a database, ensuring that each entity is represented only once to maintain data integrity.

Manual entry, on the other hand, involves the manual input of data into a system, which does not involve the sophisticated processes used in record linkage. It is more about data entry rather than establishing connections between records, and therefore does not fit within the methods that are commonly recognized for record linkage.