Errors of interpretation of p values among Spanish professional psychologists: an exploratory study
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Abstract
This paper analyzes the misinterpretatons of the p-value made by Spanish practitioner psychologists given that lack of knowledge and understanding of p value might affect the professionals’ decisions and jeopardize the quality of psychological interventions. We carried out a survey on 77 practitioner psychologists from Spain (68.8% women, mean age of 41.44 years, SD = 9.42). Our findings are consistent with previous research and suggest that many participants did not know how to correctly interpret p values. More than a third of them believed that p-value indicate the clinical or practical significance of the findings. These results highlight the importance of the training in statistical concepts, research design methodology, and statistical inference tests in order to improve professional practice among practitioner psychologists.
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