Censoring occurs when the exact time of an event is not known. There are three main types of censoring:
1. Right Censoring: When the study ends before the event occurs. 2. Left Censoring: When the event occurred before the study began. 3. Interval Censoring: When the event occurs within a known time interval but the exact time is unknown.
Handling censored data is essential as it allows for the inclusion of all available information without biasing the results. Methods like the Kaplan-Meier estimator are specifically designed to incorporate censored data.