FollowupDauer

FollowupDauer is a terminology used in clinical research and data management to describe the duration of the follow-up period for an individual participant. The term is often employed as a variable name in data dictionaries and databases, particularly in German-language contexts, but it appears in bilingual datasets as well. It represents the length of time from a defined index date, such as randomization or baseline, to a subsequent contact, visit, or endpoint assessment.

In practice, FollowupDauer is usually stored as a numeric value indicating a time interval. Common units are days, but weeks or months may also be used depending on the study protocol. The duration is often calculated as the difference between the index date and the last known contact date. When a participant is lost to follow-up, their FollowupDauer may be right-censored at the last contact date, with censoring information handled in the statistical analysis.

Usage and interpretation: FollowupDauer is a fundamental element in describing exposure time and is used to compute incidence rates per follow-up time and to perform survival analyses. It can help assess study duration, comparison of groups, and the completeness of follow-up. Data quality considerations include consistent date formats, time zones, and clear handling of missing values or early study termination.

Synonyms and variants include FollowUpDauer, Follow-up duration, and FollowUpTime. In multilingual datasets, normalization to a common unit (preferably days) is recommended to facilitate cross-study comparisons.

Example: A participant enrolled on 2023-01-01 and last contact on 2023-04-01 has a FollowupDauer of 90 days. See also: Follow-up, Duration, Censoring, Survival analysis, Data dictionary.