Sample Size in Psychological Research over the Past 30 Years

  title={Sample Size in Psychological Research over the Past 30 Years},
  author={Jacob M. Marszalek and Carolyn Barber and Julie Dawn Kohlhart and Bert H. Cooper},
  journal={Perceptual and Motor Skills},
  pages={331 - 348}
The American Psychological Association (APA) Task Force on Statistical Inference was formed in 1996 in response to a growing body of research demonstrating methodological issues that threatened the credibility of psychological research, and made recommendations to address them. One issue was the small, even dramatically inadequate, size of samples used in studies published by leading journals. The present study assessed the progress made since the Task Force's final report in 1999. Sample sizes… 

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