Word explanation and content expansion during storybook reading: Relation to SES and children’s language

We examined the relation between mothers’ word explanation and story content expansion during shared book reading, family socio-economic status (SES) and children’s language. The participants included 90 mothers and their children (aged 5–6 years) from low and middle SES. Mother–child storybook reading was videotaped, and the child’s vocabulary, storytelling and phonological awareness were tested. Results show that the mothers explained about one word during the book reading across SES, whereas story content expansion was more frequent. Children’s language and mothers’ story content expansion were correlated positively with SES, but mothers’ frequency of word explanation and manner of explanations were not correlated with SES, except for provision of word meaning, which correlated negatively with SES. Story content expansion was related to the children’s vocabulary level, whereas discussing story illustrations was negatively related to the children’s vocabulary. The limited word explanation support by mothers in shared book reading and its implications are discussed.