Table 4.

Council for Exceptional Children Evidence‐Base Classifications of Practices in Special Education

CEC Criteria
To be considered an evidence‐based the practice must meet either A or B
A	B
The practice must be supported by two methodologically sound group comparison studies with random assignment to groups, positive effects, and at least 60 total participants across studies; OR Four methodologically sound group comparison studies with nonrandom assignment to groups, positive effects, and at least 120 total participants across studies; OR Five methodologically sound single‐subject studies with positive effects and at least 20 total participants across studies.	Meet at least 50% of criteria for two or more of the study designs described in A; AND Include no methodologically sound studies conducted with negative effects and at least a 3:1 ratio of methodologically sound studies with positive effects to methodologically sound studies with neutral/mixed effects (includes group experimental, nonrandomly assigned group comparison, and single‐subject design studies collectively).

Adapted from “Council for Exceptional Children Standards for Evidence‐Based Practices in Special Education” by Cook et al., 2015, Remedial and Special Education, 36, 220–234. Copyright 2014 by the Council for Exceptional Children.