Educational taxonomies are classification schemes that organise thinking skills according to their level of complexity, providing a unifying framework and common terminology. They can be used to analyse and design educational materials, analyse students' levels of thinking and analyse and ensure alignment between learning objectives and corresponding assessment materials. There are numerous educational taxonomies that have been created and this article reviews studies that have examined their reliability, in particular Bloom's was a frequently used taxonomy.

It was found that there were very few studies specifically examining the reliability of educational taxonomies. Furthermore, where reliability was measured, this was primarily inter-rater reliability with very few studies discussing intra-rater reliability. Many of the studies reviewed provided only limited information about how reliability was calculated and the type of reliability measure used varied greatly between studies.

Finally, this article also highlights factors that influence reliability and that therefore offer potential avenues for improving reliability when using educational taxonomies, including training and practice, the use of expert raters, and the number of categories in a taxonomy. Overall it was not possible to draw conclusions about the reliability of specific educational taxonomies and it seems that the field would benefit from further targeted studies about their reliability.