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arXiv · 2308.11374

Weighting Based Approaches to Borrowing Historical Controls for Indirect comparison for Time-to-Event Data with a Cure Fraction

Jixian Wang·Hongtao Zhang·Ram Tiwari
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Abstract

To use historical controls for indirect comparison with single-arm trials, the population difference between data sources should be adjusted to reduce confounding bias. The adjustment is more difficult for time-to-event data with a cure fraction. We propose different adjustment approaches based on pseudo observations and calibration weighting by entropy balancing. We show a simple way to obtain the pseudo observations for the cure rate and propose a simple weighted estimator based on them. Estimation of the survival function in presence of a cure fraction is also considered. Simulations are conducted to examine the proposed approaches. An application to a breast cancer study is presented.

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Jixian Wang, Hongtao Zhang, Ram Tiwari. 2023-08-22. Weighting Based Approaches to Borrowing Historical Controls for Indirect comparison for Time-to-Event Data with a Cure Fraction. https://arxiv.org/abs/2308.11374

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