This meta-analysis examined the effects on reading comprehension of foundational reading skills and multicomponent reading interventions provided to students with or at risk for reading difficulties or disabilities (students with RDs) in kindergarten through Grade 3. The meta-analysis included studies identified by Wanzek et al. (2016) and Wanzek et al. (2018), with an updated search through August of 2019, for a total of 47 included studies (m = 112; total student N = 7446). The weighted average effect on norm-referenced reading comprehension outcomes was estimated as g = 0.37, indicating that primary-grade interventions have an educationally meaningful effect on reading comprehension for students with RDs. Effects did not differ for interventions focused only on foundational reading skills and those that provided both foundational skills and comprehension instruction. Effects were significantly moderated by the measurement timepoint, with follow-up effect sizes being, on average, 0.16 smaller than immediate posttest effect sizes.
Keywords: Elementary grades; Reading difficulties; Reading instruction; meta-analysis.