Skip Navigation
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

National Institute of Environmental Health Sciences

Use this QR code to view the newest version of this document
Use this QR code to view the newest version of this document

Your Environment. Your Health.

Publication Detail

Title: Impact of unequal censoring and insufficient follow-up on comparing survival outcomes: Applications to clinical studies.

Authors: Srivastava, Deo Kumar; George, E Olusegun; Lu, Zhaohua; Rai, Shesh N

Published In Stat Methods Med Res, (2021 Sep)

Abstract: Clinical trials with survival endpoints are typically designed to enroll patients for a specified number of years, (usually 2-3 years) with another specified duration of follow-up (usually 2-3 years). Under this scheme, patients who are alive or free of the event of interest at the termination of the study are censored. Consequently, a patient may be censored due to insufficient follow-up duration or due to being lost to follow-up. Potentially, this process could lead to unequal censoring in the treatment arms and lead to inaccurate and adverse conclusions about treatment effects. In this article, using extensive simulation studies, we assess the impact of such censorings on statistical procedures (the generalized logrank tests) for comparing two survival distributions and illustrate our observations by revisiting Mukherjee et al.'s1 findings of cardiovascular events in patients who took Rofecoxib (Vioxx).

PubMed ID: 34232837 Exiting the NIEHS site

MeSH Terms: Computer Simulation; Follow-Up Studies*; Humans; Proportional Hazards Models; Survival Analysis

Back
to Top