Outcomes of a universal shared reading intervention by 2 years of age: The let's read trial

Abstract

BACKGROUND: Early shared reading and literacy promotion benefits have stimulated international interest in the development of early-years literacy-promotion programs despite limited evidence of effectiveness at a broader population level.

OBJECTIVE: To determine whether a population-based primary care literacy promotion intervention during the first 2 years of life improves early markers of subsequent literacy by 2 years of age.

DESIGN AND METHODS: This cluster randomized controlled trial took place in 5 relatively disadvantaged areas in Melbourne, Australia. Infants attending their maternal and child health centers were recruited at age 1–2 months. The intervention (4–8, 12, and 18 months) comprised maternal and child health nurses modelling shared reading activities to parents, supported by parent information and free books. Outcomes (at 2 years) included expressive vocabulary (MacArthur Bates Communicative Development Inventory), communication (Communication and Symbolic Behavior Scales), and home literacy environment (StimQ-Toddler). We analyzed the outcomes using random-effects (linear regression) models allowing for clustering.

RESULTS: A total of 552 families (87.6%; 324 intervention and 228 control families) of 630 recruited families (66.5% response) were retained to outcome. A total of 97.3% of intervention parents received some (93.7% to all) of the intervention. At 2 years, the trial arms had similar vocabulary (adjusted mean difference: −2.0 [95% confidence interval: −6.2 to 2.2]; P = .36), communication (adjusted mean difference: 0.2 [95% confidence interval: −2.3 to 2.7]; P = .87), and home literacy (adjusted mean difference: −0.4 [95% confidence interval: −1.0 to 0.2]; P = .21).

CONCLUSIONS: This universal literacy-promotion program was not beneficial in relatively disadvantaged communities by the age of 2 years and may be ineffective. Alternative interpretations may relate to program intensity, reach and/or sleeper effects. Definitive outcomes at 4 years are awaited.