Found effects

The WWC found Fluency Formula™ to have potentially positive effects for fluency and potentially negative effects for 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 improvement index for fluency is +10 percentile points for the fluency outcome in the single study reviewed. The improvement index for comprehension is –11 percentile points for the comprehension outcome in the single study.

Summary

The WWC reviewed one study on Fluency Formula™. This study met WWC evidence standards. Based on this single study, the WWC found potentially positive effects in the fluency domain and potentially negative effects in the comprehension domain. The evidence presented in this report may change as new research emerges.