This meta-analysis synthesizes the literature on interventions for struggling readers in Grades 4 through 12 published between 1980 and 2011. It updates Scammacca et al.’s analysis of studies published between 1980 and 2004. The combined corpus of 82 study-wise effect sizes was meta-analyzed to determine (a) the overall effectiveness of reading interventions studied over the past 30 years, (b) how the magnitude of the effect varies based on student, intervention, and research design characteristics, and (c) what differences in effectiveness exist between more recent interventions and older ones. The analysis yielded a mean effect of 0.49, considerably smaller than the 0.95 mean effect reported in 2007. The mean effect for standardized measures was 0.21, also much smaller than the 0.42 mean effect reported in 2007. The mean effects for reading comprehension measures were similarly diminished. Results indicated that the mean effects for the 1980–2004 and 2005–2011 groups of studies were different to a statistically significant degree. The decline in effect sizes over time is attributed at least in part to increased use of standardized measures, more rigorous and complex research designs, differences in participant characteristics, and improvements in the school’s “business-as-usual” instruction that often serves as the comparison condition in intervention studies.

This synthesis extends a report of research on extensive interventions in kinder-garten through third grade (Wanzek & Vaughn, 2007) to students in Grades 4 through 12, recognizing that many of the same questions about the effectiveness of reading interventions with younger students are important to address with older students, including (a) how effective are extensive interventions in improving reading outcomes for older students with reading difficulties or disabilities and (b) what features of extensive interventions (e.g., group size, duration, grade level) are associated with improved outcomes. Nineteen studies were synthesized. Ten studies met criteria for a meta-analysis, reporting on 22 distinct treatment/comparison differences. Mean effect sizes ranged from 0.10 to 0.16 for comprehension, word reading, word reading fluency, reading fluency, and spelling outcomes. No significant differences in student outcomes were noted among studies related to instructional group size, relative number of hours of intervention, or grade level of intervention.

This meta-analysis extends previous work on extensive Tier 3 type reading interventions (Wanzek & Vaughn, 2007; Wanzek et al., 2013) to Tier 2 type interventions by examining a non-overlapping set of studies addressing the effects of less extensive reading interventions for students with or at risk for reading difficulties in Grades K-3. We examined the overall effects of these interventions on students’ foundational skills, language, and comprehension as well as the intervention features that may be associated with improved outcomes. We conducted four meta-analyses on 72 studies to examine effects on (1) standardized foundational skill measures (mean ES = 0.54), (2) not-standardized foundational skill measures (mean ES = 0.62), (3) standardized language/comprehension measures (mean ES = 0.36), and (4) not-standardized language/comprehension measures (mean ES = 1.02). There were no differences in effects related to intervention type, instructional group size, grade level, intervention implementer, or the number of intervention hours.

Over a quarter of 8th-grade students and more than one-third of 4th graders do not read well enough to understand important concepts and acquire new knowledge from grade-level text. For students with learning disabilities, the numbers are more troubling. This article describes features of evidence-based instruction for students who continue to struggle with reading in late elementary, middle, and high school. Recommendations are organized into 5 areas that are critical to the reading improvement of older struggling readers: (1) word study, (2) fluency, (3) vocabulary, (4) comprehension, and (5) motivation. Much of the content in this article reflects our efforts with the Special Education and Reading Strands at the National Center on Instruction, funded by the Office of Special Education Programs and the Office of Elementary and Secondary Education. Two reports, both available at Trained as an educational research psychologist, with expertise in quantitative methods, Dr. Roberts has directed evaluation projects of programs in education, social services, and health care. He is an external evaluator for the Reading First programs in the states of Hawaii and Oregon, and he directs evaluation of the Pihana Na Mamo project, a DOE-funded program supporting postsecondary transition of Native Hawaiian students with disabilities. He has published in multidisciplinary Tier 1 journals using structural equation models, meta-analysis, and multilevel models.

Many students at risk for or identified with reading disabilities need intensive reading interventions. This meta-analysis provides an update to the Wanzek and Vaughn synthesis on intensive early reading interventions. Effects from 25 reading intervention studies are analyzed to examine the overall effect of intensive early reading interventions as well as relationships between intervention and student characteristics related to outcomes. The weighted mean effect size (ES) estimate (ES = 0.39), with a mean effect size adjusted for publication bias (ES = 0.28), both significantly different from zero, suggested intensive early reading interventions resulted in positive outcomes for early struggling readers in kindergarten through third grades. There was no statistically significant or meaningful heterogeneity in the study-wise effect sizes. Exploratory examination of time in intervention, instructional group size, initial reading achievement, and date of publication are provided.