Impact of unequal censoring and insufficient follow-up on comparing survival outcomes: Applications to clinical studies
- 7 July 2021
- journal article
- research article
- Published by SAGE Publications in Statistical Methods in Medical Research
- Vol. 30 (9), 2057-2074
- https://doi.org/10.1177/09622802211017592
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).Funding Information
- Kentucky Council on Postsecondary Education grant (PON2 415 1900002934, PI: Chesney)
- National Institute of Health (5P20GM113226, PI: McClain; 1P42ES023716, PI: Sriva)
- American Lebanese Syrian Associated Charities
- Division of Cancer Prevention, National Cancer Institute (CA 21765)
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