RCT of a reading aloud intervention in Brazil: Do impacts differ depending on parent literacy?

Abstract Children in low- and middle-income countries (LMICs) are at risk for adverse early development and school readiness outcomes; low parent literacy is common and an important contributing factor. While prevention programs have sought to improve child outcomes by promoting positive parenting practices such as reading aloud, there has been limited evidence of whether such programs have impacts for parents with low literacy in LMICs. This study investigated: (1) whether parent literacy is associated with parent–child reading aloud interactions, the overall cognitive home environment, and child language and cognitive outcomes; and (2) whether impacts of a toddler/preschool reading aloud program differ depending on parent literacy among low-income families in northern Brazil. We performed a secondary analysis of a single-blind cluster randomized controlled trial (RCT) of a parenting intervention (Universidade do Bebe [UBB]) implemented in educational childcare centers in Boa Vista, Brazil. UBB consisted of: (1) a lending library in which children’s books were borrowed weekly; and (2) monthly parent workshops focused on reading aloud. Control families received usual care without the reading aloud program. Five hundred and six mother-infant dyads (279 intervention; 287 control) were enrolled at mean (SD) child age 37.4 (6.5) months. Parents and children were evaluated at baseline/enrollment and approximately 6–9 months later. Measures: (1) Predictor/moderator: parent literacy; (2) Parent outcomes: parent–child interaction during shared storybook reading; cognitive home environment; (3) Child outcomes: expressive and receptive vocabulary; IQ; working memory and short-term phonological memory. Analyses accounted for baseline performance, sociodemographics, and clustering within centers and sites. Parent literacy was positively associated with parent–child verbal/reading interactions and child developmental outcomes, supporting our first hypothesis, that low parent literacy would be associated with lower quantity and quality of parent–child reading and lower scores on assessments of child development. UBB had positive impacts on parent–child interaction, cognitive stimulation, IQ, and receptive vocabulary for both high and low literacy parents, contrary to our second hypothesis, that low parent literacy would be associated with reductions in impacts of the reading aloud intervention. The comparable impacts of a reading aloud program on parent–child verbal/reading interactions and child cognitive outcomes regardless of parent literacy level suggest that preventive interventions in LMICs should consider promotion of shared reading even for low-literacy families.