Publications by authors named "Hezhi Lu"

A common and important problem in medicine, economics and environmental studies is the comparison of the variances of several treatments with that of a control treatment. Among the existing methods, Spurrier's optimal test based on multivariate F distribution has exact type I error rates. However, it requires equal sample sizes among the treatment groups.

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Interval estimation with accurate coverage for risk difference (RD) in a correlated 2 × 2 table with structural zero is a fundamental and important problem in biostatistics. The score test-based and Bayesian tail-based confidence intervals (CIs) have good coverage performance among the existing methods. However, as approximation approaches, they have coverage probabilities lower than the nominal confidence level for finite and moderate sample sizes.

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Non-inferiority of one treatment to another based on odds ratio for the matched-pair design is a common issue in the medical research. Liu et al. derived two asymptotic tests, delta method and score test, which can be applicable for large samples but may tend to be liberal for small sample sizes.

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Article Synopsis
  • A new statistical framework for three-arm non-inferiority trials was proposed to improve upon the traditional two-arm trials, which include a placebo and a predefined non-inferiority margin.
  • The authors' method enhances the testing process by using unbiased pooled estimators for variance and employing intersection-union tests for rejection rules.
  • The results demonstrate that their approach outperforms Hida and Tango's method in larger samples and shows superior performance in small to moderate samples, achieving higher statistical power while maintaining control over type I error rates.
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