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How to Select, Calculate, and Interpret Effect Sizes
Abstract
The objective of this article is to offer guidelines regarding the selection, calculation, and interpretation of effect sizes (ESs). To accomplish this goal, ESs are first defined and their important contribution to research is emphasized. Then different types of ESs commonly used in group and correlational studies are discussed. Several useful resources are provided for distinguishing among different types of effects and what modifications might be required in their calculation depending on a study's purpose and methods. This article should assist producers and consumers of research in understanding the role, importance, and meaning of ESs in research reports.
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Systematic Reviews and Cancer Research: a Suggested Stepwise Approach
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“Given the small sample size the following bias correction was performed [47]: (1) where n = n 1 + n 2 .”
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“Mean difference scores were tested using paired samples t-tests and converted into corrected standardised effect sizes (Hedges’ g ; Durlak, 2009).”
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Metadata
- Authors
- Durlak, J. A.
- Venue
- Journal of Pediatric Psychology
- Publisher
- Oxford University Press (OUP)
- Published
- 2009-02-16
- Volume
- 34
- Issue
- 9
- Pages
- 917-928
- ISSN
- 0146-8693 (ISSN-L)
- 1465-735X
- OpenAlex
- W2152193038
- Cited by
- 1,446
- References
- 8
- FWCI
- 17.91
- Type
- journal article
- Language
- en
- Open access
- closed
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