What Works Clearinghouse (WWC)

https://ies.ed.gov/ncee/wwc/

Funded by the Institute of Education Sciences, the WWC is “a central and trusted source of scientific evidence for what works in education” and publishes intervention reports that assess research on beginning reading programs. WWC evaluations translate effect sizes from research into improvement index scores to reflect the average change in a student’s percentile rank that can be expected if the student has the intervention.

In 2007, 2008, and in July 2013, the WWC examined research on Reading Recovery and accepted studies that met its evidence standards. Reading Recovery received positive or potentially positive ratings across all four domains: alphabetics (phonics and phonemic awareness), fluency, comprehension, and general reading achievement. Among all programs reviewed, Reading Recovery received the highest rating in general reading achievement. See how Reading Recovery compares to other interventions.