Optimizing Time in Isolated Phonemic Awareness Instruction: A Meta-Analysis of Cumulative Dosage for Improved Reading Outcomes

Purpose This study examined the optimal cumulative dosage of isolated phonemic awareness (PA) instruction for improving reading outcomes in preschool through first grade. Although PA is a foundational reading skill, its impact on word reading may follow a nonlinear pattern. We estimated the dosage associated with the greatest reading gains and explored whether instructional features and child characteristics moderate these effects.Method Fifteen randomized and quasi-experimental studies (46 effect sizes) were included. Across studies (N = 1,202), samples were kindergarten (67%), preschool (21.5%) and first grade (11.6%) participants (Mage = 5.6 years, based on available data reported in 5 of 15 studies). Of participants, 47.7% were female (reported in 12 studies). 13 studies were conducted in English, 1 Spanish, and 1 German. Effect sizes were calculated using Hedges’ g, and mixed-effects nonlinear models estimated the maximum effect size and optimal cumulative dosage.Results A nonlinear relationship emerged between cumulative dosage and reading outcomes, with the maximum effect (g = 0.27, p = .046) occurring at 5.35 hours. However, wide confidence intervals indicate this estimate should be interpreted descriptively rather than prescriptively. Instruction targeting segmenting and blending showed a higher peak (g = 0.37). Children not at risk of reading difficulties showed larger gains than at-risk peers, whose gains diminished at higher dosages.Conclusion Brief isolated PA instruction supports reading, particularly when including segmenting and blending activities. There is no empirical evidence demonstrating that extended, letter-free PA instruction yields improvements in reading outcomes, including for children at risk of reading difficulty.