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Calculating and reporting effect sizes to facilitate cumulative science

A practical primer for t-tests and Anovas

Bibliographic Data

ID23313814
AuthorsDaniël Lakens (0000-0002-0247-239X, Eindhoven University of Technology, corresponding author)
Year2013
Volume4
Pages863-863
Publication date2013-01-01
Peer ReviewedYes
Open AccessYes
TypeARTICLE
VenueFrontiers in Psychology (JOURNAL)
Journal identifiersISSN: 1664-1078 • E-ISSN: 1664-1078
PublisherFrontiers Media SA (PUBLISHER • CH)
DOI10.3389/fpsyg.2013.00863
PMID24324449
OpenAlexW2137070227
LanguageEN
Citations received1.062
References cited22

Effect sizes are the most important outcome of empirical studies. Most articles on effect sizes highlight their importance to communicate the practical significance of results. For scientists themselves, effect sizes are most useful because they facilitate cumulative science. Effect sizes can be used to determine the sample size for follow-up studies, or examining effects across studies. This article aims to provide a practical primer on how to calculate and report effect sizes for t-tests and ANOVA's such that effect sizes can be used in a-priori power analyses and meta-analyses. Whereas many articles about effect sizes focus on between-subjects designs and address within-subjects designs only briefly, I provide a detailed overview of the similarities and differences between within- and between-subjects designs. I suggest that some research questions in experimental psychology examine inherently intra-individual effects, which makes effect sizes that incorporate the correlation between measures the best summary of the results. Finally, a supplementary spreadsheet is provided to make it as easy as possible for researchers to incorporate effect size calculations into their workflow.

Analysis of variance · Design of experiments · Meta-analysis · Repeated measures design · Sample size determination · Statistical hypothesis testing · Statistical power · Statistics · Variance (accounting) · Behavioral Health and Interventions · Computer Science · Mathematics · Medicine · Mental Health Research Topics · Meta-analysis and systematic reviews · Psychology

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Unique citing works1.062
Citations per year88,5
Citation span2014 - 2026 (13)
Citation velocitycurrent
Highly citedYes
Citation typesNeutral: 940
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