Affiliation:
1. Department of Communication Sciences and Disorders, California State University, Sacramento
2. Department of Human Development and Family Studies, Colorado State University, Fort Collins
Abstract
Purpose
The purpose was to examine and determine effect size distributions reported in published audiology and speech-language pathology research in order to provide researchers and clinicians with more relevant guidelines for the interpretation of potentially clinically meaningful findings.
Method
Cohen's
d,
Hedges'
g,
Pearson
r,
and sample sizes (
n
= 1,387) were extracted from 32 meta-analyses in journals in speech-language pathology and audiology. Percentile ranks (25th, 50th, 75th) were calculated to determine estimates for small, medium, and large effect sizes, respectively. The median sample size was also used to explore statistical power for small, medium, and large effect sizes.
Results
For individual differences research, effect sizes of Pearson
r
= .24, .41, and .64 were found. For group differences, Cohen's
d
/Hedges'
g
= 0.25, 0.55, and 0.93. These values can be interpreted as small, medium, and large effect sizes in speech-language pathology and audiology. The majority of published research was inadequately powered to detect a medium effect size.
Conclusions
Effect size interpretations from published research in audiology and speech-language pathology were found to be underestimated based on Cohen's (1988, 1992) guidelines. Researchers in the field should consider using Pearson
r
= .25, .40, and .65 and Cohen's
d
/Hedges'
g
= 0.25, 0.55, and 0.95 as small, medium, and large effect sizes, respectively, and collect larger sample sizes to ensure that both significant and nonsignificant findings are robust and replicable.
Publisher
American Speech Language Hearing Association
Subject
Speech and Hearing,Linguistics and Language,Language and Linguistics
Cited by
43 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献