Researchers who do not have adequate statistical knowledge commit a wide range of critical errors with regard to the design, execution,analysis, presentation and interpretation of their studies. The aim of the present work is to examine the statistical errors of scientific articles. Cross sectional study. Methods: Ninety-five articles published in either Science Citation Index (SCI) or (Science Citation Index-Expanded) SCI-E journals, 122 articles published in non-SCI or non-SCI-E journals were included in this study. The articles were chosen from among those indexed in the PubMed and Bioline databases between the years 2004 and 2010, inclusively. A total of 217 articles had at least one statistical error. The most frequently encountered statistical error was "errors in summarizing data" for articles published in the journals indexed in SCI or SCI-E, as well as non-SCI or non-SCI-E journals. For errors involving "use of an incorrect test" and "statistical symbol errors", there was a statistically significant difference between articles published in journals indexed in SCI or SCI-E and non-SCI or non-SCI-E journals; this difference favored the former. Some action should be taken by researchers and editors to prevent the introduction of statistical errors into scientific publications. Researchers (i) should have a basic statistical knowledge, (ii) should consult a biostatistician at the planning, analyzing, interpreting and reporting stages of a study. Furthermore, editors should send studies that have been submitted to their journal to a biostatistician during the review process.