Analysis of repeated measurements in physical therapy research

Research output: Contribution to journalArticleResearchpeer-review

48 Citations (Scopus)

Abstract

In this paper, I attempt to introduce physical therapists to the most common statistical tests for analysing differences between repeated measurements over time. Using the example of 'whole-body flexibility' recorded at six different times of day and the Statistical Package for the Social Sciences (SPSS), I discuss the advantages and disadvantages of the various approaches for analysing a simple one-factor design. The most important issues in test selection for repeated measures are the exploration of, and correction for, the violation of 'sphericity' when employing a univariate general linear model (GLM), as well as the sample size when adopting a multivariate GLM. I summarize current advice on choice of test with the aid of a 'decision tree', based on the results of documented statistical simulations which have investigated how the various statistical tests 'perform' in certain situations. Lastly, I comment on the most appropriate ways to present and interpret data drawn from serial measurements.

Original languageEnglish
Pages (from-to)194-208
Number of pages15
JournalPhysical Therapy in Sport
Volume2
Issue number4
DOIs
Publication statusPublished - 1 Jan 2001

Fingerprint

Linear Models
Decision Trees
Social Sciences
Physical Therapists
Research
Sample Size
Therapeutics

Cite this

@article{1fb325dbe88e4274bcb4189735e1a911,
title = "Analysis of repeated measurements in physical therapy research",
abstract = "In this paper, I attempt to introduce physical therapists to the most common statistical tests for analysing differences between repeated measurements over time. Using the example of 'whole-body flexibility' recorded at six different times of day and the Statistical Package for the Social Sciences (SPSS), I discuss the advantages and disadvantages of the various approaches for analysing a simple one-factor design. The most important issues in test selection for repeated measures are the exploration of, and correction for, the violation of 'sphericity' when employing a univariate general linear model (GLM), as well as the sample size when adopting a multivariate GLM. I summarize current advice on choice of test with the aid of a 'decision tree', based on the results of documented statistical simulations which have investigated how the various statistical tests 'perform' in certain situations. Lastly, I comment on the most appropriate ways to present and interpret data drawn from serial measurements.",
author = "Greg Atkinson",
year = "2001",
month = "1",
day = "1",
doi = "10.1054/ptsp.2001.0071",
language = "English",
volume = "2",
pages = "194--208",
journal = "Physical Therapy in Sport",
issn = "1873-1600",
publisher = "Elsevier BV",
number = "4",

}

Analysis of repeated measurements in physical therapy research. / Atkinson, Greg.

In: Physical Therapy in Sport, Vol. 2, No. 4, 01.01.2001, p. 194-208.

Research output: Contribution to journalArticleResearchpeer-review

TY - JOUR

T1 - Analysis of repeated measurements in physical therapy research

AU - Atkinson, Greg

PY - 2001/1/1

Y1 - 2001/1/1

N2 - In this paper, I attempt to introduce physical therapists to the most common statistical tests for analysing differences between repeated measurements over time. Using the example of 'whole-body flexibility' recorded at six different times of day and the Statistical Package for the Social Sciences (SPSS), I discuss the advantages and disadvantages of the various approaches for analysing a simple one-factor design. The most important issues in test selection for repeated measures are the exploration of, and correction for, the violation of 'sphericity' when employing a univariate general linear model (GLM), as well as the sample size when adopting a multivariate GLM. I summarize current advice on choice of test with the aid of a 'decision tree', based on the results of documented statistical simulations which have investigated how the various statistical tests 'perform' in certain situations. Lastly, I comment on the most appropriate ways to present and interpret data drawn from serial measurements.

AB - In this paper, I attempt to introduce physical therapists to the most common statistical tests for analysing differences between repeated measurements over time. Using the example of 'whole-body flexibility' recorded at six different times of day and the Statistical Package for the Social Sciences (SPSS), I discuss the advantages and disadvantages of the various approaches for analysing a simple one-factor design. The most important issues in test selection for repeated measures are the exploration of, and correction for, the violation of 'sphericity' when employing a univariate general linear model (GLM), as well as the sample size when adopting a multivariate GLM. I summarize current advice on choice of test with the aid of a 'decision tree', based on the results of documented statistical simulations which have investigated how the various statistical tests 'perform' in certain situations. Lastly, I comment on the most appropriate ways to present and interpret data drawn from serial measurements.

UR - http://www.scopus.com/inward/record.url?scp=0035168631&partnerID=8YFLogxK

U2 - 10.1054/ptsp.2001.0071

DO - 10.1054/ptsp.2001.0071

M3 - Article

VL - 2

SP - 194

EP - 208

JO - Physical Therapy in Sport

JF - Physical Therapy in Sport

SN - 1873-1600

IS - 4

ER -