Cited by 97Statistical Methods in Clinical TrialsStatistical Methods and Bayesian InferenceStatistical Methods in Epidemiology

Sample size calculation for comparing two negative binomial rates

Zhu, Haiyuan, Lakkis, Hassan·2014·Statistics in Medicine

Abstract

Negative binomial model has been increasingly used to model the count data in recent clinical trials. It is frequently chosen over Poisson model in cases of overdispersed count data that are commonly seen in clinical trials. One of the challenges of applying negative binomial model in clinical trial design is the sample size estimation. In practice, simulation methods have been frequently used for sample size estimation. In this paper, an explicit formula is developed to calculate sample size based on the negative binomial model. Depending on different approaches to estimate the variance under null hypothesis, three variations of the sample size formula are proposed and discussed. Important characteristics of the formula include its accuracy and its ability to explicitly incorporate dispersion parameter and exposure time. The performance of the formula with each variation is assessed using simulations.

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Crossref · 10.1002/sim.5947

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Authors
Zhu, H., & Lakkis, H.
Affiliations
Forest Laboratories (United States) (US)
Corresponding author
Zhu, Haiyuan
Venue
Statistics in Medicine
Publisher
Wiley
Published
2013-08-23
Volume
33
Issue
3
Pages
376-387
ISSN
0277-6715 (ISSN-L)
OpenAlex
W2147657405
Cited by
97
References
13
Citations by year
2026: 8 · 2025: 6 · 2024: 9 · 2023: 6 · 2022: 8 · 2021: 19 · 2020: 12 · 2019: 8 · 2018: 8 · 2017: 4 · 2016: 2 · 2015: 2 · 2014: 5
FWCI
2.65
Type
journal article
Language
en
Open access
closed
Locations
  • Statistics in Medicine (publishedVersion)
  • PubMed (publishedVersion)
Topics
  • Physical Sciences › Mathematics › Statistics and Probability › Statistical Methods in Clinical Trials
  • Physical Sciences › Mathematics › Statistics and Probability › Statistical Methods and Bayesian Inference
  • Physical Sciences › Mathematics › Statistics and Probability › Statistical Methods in Epidemiology
Keywords
sample size determination, negative binomial regression, count data, overdispersion, clinical trial design, dispersion parameter, exposure time, explicit formula
MeSH terms
Tiotropium Bromide, Asthma, Clinical Trials as Topic, Computer Simulation, Humans, Scopolamine Derivatives, Models, Statistical, Likelihood Functions, Sample Size

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