Cited by 306Statistical Methods in Clinical TrialsStatistical Methods and Bayesian InferenceStatistical Methods in Epidemiology

Sample Size Calculations for Studies with Correlated Observations

Liu, Guanghan, Liang, Kung-Yee·1997·Biometrics

Abstract

Correlated data occur frequently in biomedical research. Examples include longitudinal studies, family studies, and ophthalmologic studies. In this paper, we present a method to compute sample sizes and statistical powers for studies involving correlated observations. This is a multivariate extension of the work by Self and Mauritsen (1988, Biometrics 44, 79-86), who derived a sample size and power formula for generalized linear models based on the score statistic. For correlated data, we appeal to a statistic based on the generalized estimating equation method (Liang and Zeger, 1986, Biometrika 73, 13-22). We highlight the additional assumptions needed to deal with correlated data. Some special cases that are commonly seen in practice are discussed, followed by simulation studies.

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Authors
Liu, G., & Liang, K.-Y.
Affiliations
  • Merck & Co., Inc., Rahway, NJ, USA (United States) (US)
  • Johns Hopkins University (US)
Venue
Biometrics
Publisher
JSTOR
Published
1997-09
Volume
53
Issue
3
Pages
937
ISSN
0006-341X (ISSN-L)
OpenAlex
W1970913176
Cited by
306
References
19
Citations by year
2026: 13 · 2025: 11 · 2024: 8 · 2023: 10 · 2022: 16 · 2021: 12 · 2020: 21 · 2019: 30 · 2018: 16 · 2017: 17 · 2016: 13 · 2015: 14 · 2014: 13 · 2013: 13 · 2012: 9
FWCI
2.94
Type
journal article
Language
en
Open access
closed
Locations
  • Biometrics (publishedVersion)
  • PubMed (publishedVersion)
Funders
National Institute of General Medical Sciences (GM49909, R01GM049909)
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, statistical power, correlated observations, generalized estimating equations, longitudinal data, family studies, generalized linear models, score statistic
MeSH terms
Biometry, Family, Humans, Longitudinal Studies, Monte Carlo Method, Ophthalmology, Regression Analysis, Research Design, Models, Statistical

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