[1] In contrast to that view, the paper described a series of opinionated subjective decisions which the WWC made about providing some educational research and declining to index another sort.
[2] The WWC recommendations for interpreting the results of single-case educational studies is the subject of discussion.
[3][4][5] The WWC has systems for evaluating the effectiveness of educational research in general[6] and curricula.
[8] Some of the concerns expressed about WWC are that it appears to have difficulty keeping up with the research so it may not be current; and when a program is not listed on their database, it may be that it did not meet their criteria or they have not yet reviewed it, but it's not clear which.
[9] In addition Straight Talk on Evidence, authored by the Arnold Ventures LLC’ Evidence-Based Policy team , on January 16, 2018 expressed concerns about the validity of the ratings provided by WWC.