A sizable body of studies documents that shared storybook reading is a key activity for vocabulary acquisition in early childhood. In four studies, the present dissertation has addressed research gaps that are pivotal for advancing environmental models of literacy development and for language education practice.
I developed and validated recognition tests for the objective assessment of shared storybook reading and adult leisure reading, and I investigated their relationships with questionnaire measures and preschoolers’ lower level language (LLL) and higher level language (HLL) skills. To explore the potential of shared storybook reading for fostering preschoolers’ oral language skills, I also developed a narrative dialogic reading intervention with wordless picture books that was employed in an intervention study in order to gain new insights regarding the implementability and individual effectiveness of dialogic reading as well as the specifity, magnitude, and sustainability of intervention effects on vocabulary and narrative skills.
The Home Literacy Model (Sénéchal & LeFevre, 2002, 2014) oversimplifies the roles and interplay of children, caregivers, and storybooks in shared reading activities. Due to linguistic characteristics of storybooks and extratextual talk, shared reading has the potential to facilitate the acquisition of different oral language skills that in turn predict reading comprehension in primary school.
Therefore, this dissertation has aimed to scrutinize which LLL and HLL skills can be fostered through shared storybook reading. Studies 1 and 2 established the methodological basis by validating two recognition tests that measure exposure to storybooks and adult literature, respectively. Studies 3 and 4 investigated effects of shared storybook reading in the home literacy environment (HLE) and the child care literacy environment (CCLE) on preschoolers’ LLL and HLL skills.
In study 1, a newly developed storybook title recognition test (TRT-VS;
adapted from Sénéchal et al., 1996) for four- to seven-year-old children and their caregivers was validated. Each of the two parallel test forms consists of 20 titles of popular storybooks and, in order to control for guessing, ten fake storybook titles.
Psychometric analyses, correlation analyses, and structural equation models indicated that the TRT-VS is an objective, reliable, and valid test for assessing storybook exposure in preschoolers and their parents. The TRT-VS can be completed by preschoolers as an audio decision task, allowing a direct estimation of their storybook exposure. In a structural equation model, a latent TRT variable (child TRT-VS and parent TRT-VS) explained about 46% of variance in phonological awareness skills and about 53% of variance in vocabulary skills. In the same model, a latent SES and a latent HLE questionnaire variable did not explain a significant amount of variance in these early literacy skills. Thus, the storybook TRT is a proximal measure of shared reading experiences that can be used for investigating the relation between shared storybook reading and the development of oral language skills. Consequently, the TRT-VS was used in study 3 as a measure of the storybook exposure of preschoolers, parents, and child care workers. In study 4, the TRT-VS was used to control for children’s non-intervention storybook exposure and to evaluate whether effects of the narrative dialogic reading intervention are moderated by non-intervention storybook exposure.
Study 2 validated a newly developed author recognition test (ART; adapted from Stanovich & West, 1989) for 13- to 80-year-old readers. Each of the two parallel test forms consists of 50 names of bestselling authors and 25 fake author names. Psychometric analyses and an explanatory item response analysis showed that the ART is an objective, reliable, and valid measure for the assessment of print exposure across the reading life span. Therefore, the German ART can be used for the assessment of caregivers’ leisure reading amount. In study 2, the print exposure of readers increased with age. Moreover, author recognition probability was negatively related to the author mean publication year. Most importantly, participant age moderated the effect of author mean publication year on author recognition probability: The recognition probability of classic authors increased between age 15 and age 65. By contrast, the recognition probability of recent authors increased only between age 15 and age 45 and did not change between age 45 and age 65. This indicates that the mean publication year is a key author variable
in the ART that should be taken into account when print exposure is assessed in age-diverse reader populations, especially if readers older than 45 years participate.
Study 3 examined to which extent different measures of shared reading and literacy environments contribute to preschoolers’ storybook exposure and their LLL and HLL skills. Parents’ storybook exposure explained about 10% of variance in preschoolers’ storybook exposure. Three measures explained unique variance in vocabulary skills: a questionnaire that assesses activities and resources in the CCLE, parents’ storybook exposure, and children’s storybook exposure. By contrast, only parents’ and preschoolers’ storybook exposure explained unique variance in grammar skills. Finally, preschoolers’ storybook exposure was the only unique predictor of the HLL skills comprehension monitoring and narrative comprehension. Interaction terms between parent and child care worker variables did not account for a significant amount of variance in children’s storybook exposure or oral language skills, suggesting that the contributions of the two literacy environments are additive rather than multiplicative.
Study 4 tested the effects of a narrative dialogic reading intervention on different vocabulary and narrative skills of five-year-olds. Drawing on results from experimental shared reading research, the intervention was modified to increase children’s engagement, provide stimulation on different levels of comprehension, and facilitate the acquisition of narrative skills. For the assessment of narrative comprehension and production skills, we developed coding schemes based on wordless picture books (see Appendix D). The intervention had small short-term effects on LLL and HLL skills, and the effect on one HLL skill (inferential narrative comprehension) was maintained after five months. Comparisons between the dialogic reading group, the music treatment group, and the no treatment group yielded that the music treatment did not improve oral language skills. Thus, the effects were specifically due to the contents of the dialogic reading intervention.
Individual differences in children’s non-intervention storybook exposure and cognitive abilities were also significant predictors of language development but did not moderate intervention gains. There were no transfer effects on narrative production skills. Together, the results provide new evidence that narrative dialogic reading can be used to foster both LLL and HLL skills in typically developing children.