The overarching objective of this thesis is to examine how we best can predict, facilitate and support the development of reading comprehension. The three studies that make up this thesis are based on longitudinal and experimental data.
The first study is a systematic review (meta—analysis) that includes 64 studies ofpreschool predictors of later reading comprehension ability. The results of this study showed that a large amount (59.7%) ofthe individual variance in reading comprehension is explained by early language ability and code—related skills (i.e., related to decoding).
The second study is a 6-year longitudinal study in which 215 Norwegian children were followed annually from the age of 4 years to the age of 9 years. Using latent growth curve modelling, two pathways to reading comprehension were identified: language comprehension and decoding ability. Together these accounted for 99.7% of the variance in reading comprehension at age 7. In addition, language comprehension also predicted the students” growth trajectories.
The third study is a quasi—experimental study with third- and fourth—grade students who were poor readers. The students in the intervention group received an lO-week intervention that focused on word knowledge, while the students in the control group received the usual instruction. The students in the intervention group made significant improvements in their language and reading comprehension abilities as compared to the control group.
A key finding is on the importance ofa broad focus on language beginning at an early age and continuing until school age as early language skills were an important predictor of later reading comprehension ability in Study 1 and 2. In addition, as seen in Study 3, teaching third-and fourth-grade students knowledge of word forms and meanings supported the development of language comprehension and reading comprehension. Although we still do not know enough about the complexity of reading comprehension and the underlying components, deduced from the results in this thesis; language ability stands out as vital.