The Evidence on Teaching

Effectiveness of Reading-Strategy Interventions in Whole Classrooms: A Meta-Analysis

Okkinga, M., van Steensel, R., van Gelderen, A. J. S., et al. · 2018

grade Cmeta-analysisindependentmixed
Sample
52 studies / 125 effect sizes
Population
Whole-classroom reading-strategy interventions, school-age.
Design
Meta focused on ecologically valid whole-class delivery; separates standardized from researcher-developed outcomes and researcher- vs teacher-delivery.
Key findings
Under realistic whole-class delivery, strategy instruction moves standardized comprehension only d=0.19 (vs 0.43 on researcher-made tests), and effects shrink further when teachers rather than researchers deliver. The honest at-scale estimate is ~0-0.19.
Genetic confound
Experimental base; effects inflate when the researcher (not the teacher) delivers.
Replication notes
Quantifies the whole-class/teacher-delivered deflation the older 0.32 anchor missed.

Effects

OutcomeMetricValueMeasureTimingVsHorizonClass
Comprehension (standardized measures)d0.186standardizedend-of-treatmentbusiness-as-usualend-of-treatmentdomain-skill
Comprehension (researcher-developed measures)d0.431researcher-designedend-of-treatmentbusiness-as-usualend-of-treatmentdomain-skill
Strategic-ability outcomesd0.786researcher-designedend-of-treatmentbusiness-as-usualend-of-treatmentnear-transfer

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