Variance components and their implications for statistical information in medical data

E. J. Orav, Thomas Louis, R. H. Palmer, E. A. Wright

Research output: Contribution to journalArticle

Abstract

We discuss general issues concerning the design and analysis of medical experiments involving repeated measures or hierarchical groupings of subjects within larger study units. Depending on the types of questions being investigated, the correlations induced by clustering can have dramatic impact on the effective sample size. The unique aspects of such experiments must be accounted for during analysis and during interpretation of the results. We illustrate these issues by using a variance components model to investigate the role of leadership in medical practice.

Original languageEnglish (US)
Pages (from-to)599-616
Number of pages18
JournalStatistics in Medicine
Volume10
Issue number4
DOIs
StatePublished - 1991
Externally publishedYes

Fingerprint

Variance Components
Sample Size
Cluster Analysis
Effective Sample Size
Variance Component Model
Repeated Measures
Leadership
Grouping
Experiment
Clustering
Unit
Interpretation
Design

ASJC Scopus subject areas

  • Epidemiology
  • Statistics and Probability

Cite this

Variance components and their implications for statistical information in medical data. / Orav, E. J.; Louis, Thomas; Palmer, R. H.; Wright, E. A.

In: Statistics in Medicine, Vol. 10, No. 4, 1991, p. 599-616.

Research output: Contribution to journalArticle

Orav, E. J. ; Louis, Thomas ; Palmer, R. H. ; Wright, E. A. / Variance components and their implications for statistical information in medical data. In: Statistics in Medicine. 1991 ; Vol. 10, No. 4. pp. 599-616.
@article{3e74d76abb424ee8b11b42bb3b8009e9,
title = "Variance components and their implications for statistical information in medical data",
abstract = "We discuss general issues concerning the design and analysis of medical experiments involving repeated measures or hierarchical groupings of subjects within larger study units. Depending on the types of questions being investigated, the correlations induced by clustering can have dramatic impact on the effective sample size. The unique aspects of such experiments must be accounted for during analysis and during interpretation of the results. We illustrate these issues by using a variance components model to investigate the role of leadership in medical practice.",
author = "Orav, {E. J.} and Thomas Louis and Palmer, {R. H.} and Wright, {E. A.}",
year = "1991",
doi = "10.1002/sim.4780100411",
language = "English (US)",
volume = "10",
pages = "599--616",
journal = "Statistics in Medicine",
issn = "0277-6715",
publisher = "John Wiley and Sons Ltd",
number = "4",

}

TY - JOUR

T1 - Variance components and their implications for statistical information in medical data

AU - Orav, E. J.

AU - Louis, Thomas

AU - Palmer, R. H.

AU - Wright, E. A.

PY - 1991

Y1 - 1991

N2 - We discuss general issues concerning the design and analysis of medical experiments involving repeated measures or hierarchical groupings of subjects within larger study units. Depending on the types of questions being investigated, the correlations induced by clustering can have dramatic impact on the effective sample size. The unique aspects of such experiments must be accounted for during analysis and during interpretation of the results. We illustrate these issues by using a variance components model to investigate the role of leadership in medical practice.

AB - We discuss general issues concerning the design and analysis of medical experiments involving repeated measures or hierarchical groupings of subjects within larger study units. Depending on the types of questions being investigated, the correlations induced by clustering can have dramatic impact on the effective sample size. The unique aspects of such experiments must be accounted for during analysis and during interpretation of the results. We illustrate these issues by using a variance components model to investigate the role of leadership in medical practice.

UR - http://www.scopus.com/inward/record.url?scp=0025844909&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0025844909&partnerID=8YFLogxK

U2 - 10.1002/sim.4780100411

DO - 10.1002/sim.4780100411

M3 - Article

C2 - 2057658

AN - SCOPUS:0025844909

VL - 10

SP - 599

EP - 616

JO - Statistics in Medicine

JF - Statistics in Medicine

SN - 0277-6715

IS - 4

ER -