A review of studies analyzing the statistical knowledge of primary schoolchildren (6-12 years old) is carried out. Based on a review in JCR/SSCI, Scopus, Eric, Google Scholar, Science Direct, World Scientific, Springer, and Wiley Online library, 18 articles (2003-2021) have been identified and analyzed based on two objectives: (1) to identify the different study approaches and (2) to analyze the elements of statistical knowledge. The results show that almost half of the investigations were carried out based on one of the following approaches: the Toulmin approach (TM), the statistical mathematical working space (SMWS), the structure of observed learning outcomes (SOLO) taxonomy and Curcio's graph reading levels (CGRL). It is concluded that CGRL is the most common approach and statistical graphs are the most analyzed statistical objects.