- José Manuel Caperos: Faculty of Humanities and Social Sciences, Comillas Pontifical University, Madrid, Spain. jcaperos@upcomillas.es
BACKGROUND: Recent reviews have drawn attention to frequent consistency errors when reporting statistical results.
METHOD: We have reviewed the statistical results reported in 186 articles published in four Spanish psychology journals. Of these articles, 102 contained at least one of the statistics selected for our study: Fisher-F , Student-t and Pearson-c 2 .
RESULTS: Out of the 1,212 complete statistics reviewed, 12.2% presented a consistency error, meaning that the reported p-value did not correspond to the reported value of the statistic and its degrees of freedom. In 2.3% of the cases, the correct calculation would have led to a different conclusion than the reported one. In terms of articles, 48% included at least one consistency error, and 17.6% would have to change at least one conclusion. In meta-analytical terms, with a focus on effect size, consistency errors can be considered substantial in 9.5% of the cases.
CONCLUSION: These results imply a need to improve the quality and precision with which statistical results are reported in Spanish psychology journals.