Found effects

The WWC found Failure Free Reading to have no discernible effects on alphabetics and fluency, and potentially positive effects on comprehension.

Improvement index

The WWC computes an improvement index for each individual finding. In addition, within each outcome domain, the WWC computes an average improvement index for each study and an average improvement index across studies (see Technical Details of WWC-Conducted Computations). The improvement index represents the difference between the percentile rank of the average student in the intervention condition versus the percentile rank of the average student in the comparison condition. Unlike the rating of effectiveness, the improvement index is based entirely on the size of the effect, regardless of the statistical significance of the effect, the study design, or the analyses. The improvement index can take on values between -50 and +50, with positive numbers denoting results favorable to the intervention group.

The average improvement index for alphabetics is +1 percentile points across all findings in the single study, with a range of –3 to +7 percentile points. The average improvement index for fluency is +2 percentile points for the single outcome. The average improvement index for comprehension is +10 percentile points across all findings in the single study, with a range of +7 to +14 percentile points.

Summary

The WWC reviewed 59 studies on Failure Free Reading. One study met the WWC evidence standards. Based on this one study, the WWC found no discernible effects on alphabetics and fluency and potentially positive effects on comprehension. The evidence presented in this report may change as new research emerges.