Teaching Secondary Students to Write Effectively

level of evidence

 assigned to each 

recommendation indicates the strength of 

the evidence for the effect of the practices 

on student achievement, based on studies 

published since 1995 or published prior to 

1995 and recommended by the panel.

The panel and Mathematica WWC staff 

assigned a level of evidence to each recom-

mendation based on an assessment of the 

relevant evidence supporting each recom-

mendation. Table 1 shows the level of evi-

dence rating for each recommendation as 

determined by WWC criteria outlined in Table 

A.1 in Appendix A. (Appendix D presents 

more information on the body of evidence 

supporting each recommendation.)