Background: Morphological analysis skill is the ability to problem-solve meanings of unfamiliar words by applying knowledge of morphological constituents. For vocabulary words from the academic layer of English, the major, meaning-carrying morphological contituents are Latin roots (nov meaning ‘new’ in innovative). The degree to which morphological analysis skill using Latin roots is susceptible to intervention and whether improvements relate to reading comprehension remains unclear. Methods: We investigated the effects of a morphology intervention designed to promote academic vocabulary learning, morphological analysis and reading comprehension with 140 adolescent, multilingual learners in US schools (intervention n = 70; comparison n = 70). We estimated direct effects of the intervention on morphological analysis and academic vocabulary knowledge and examined whether they mediate intervention effects on reading comprehension. Academic vocabulary was measured as both definitional and multidimensional knowledge. Results: We found significant, direct effects of the intervention on morphological analysis skill and academic vocabulary knowledge. Additionally, we found a significant indirect effect on reading comprehension via academic vocabulary and a marginally significant indirect effect via morphological analysis skill. Notably, the indirect effect of academic vocabulary was evident only for multidimensional, not definitional knowledge. Conclusions: Findings extend current understanding about how morphology intervention promotes vocabulary and reading comprehension improvement for multilingual learners. (word count = 207). Highlights: What is already known about this topic The ability to figure out word meanings through morphological analysis relates to improvements in vocabulary knowledge. Studies have focused on prefixes and suffixes. However, the main meaning-carrying components of vocabulary words from the academic layer of English are Latin roots (min meaning ‘small’ in diminish). Much less is known about whether carefully designed interventions focused on Latin roots can affect morphological analysis skill, academic vocabulary knowledge and, in turn, reading comprehension. What this paper adds Intervention can improve multilingual learners' ability to improve vocabulary through analysis of morphological relations using Latin roots (e.g., min in diminish, miniscule and minor). Intervention may have indirect effects on reading comprehension through morphological analysis and improved academic vocabulary knowledge. Both definitional and multidimensional vocabulary knowledge are improved through intervention, but only multidimensional knowledge relates to improvements in comprehension. Implications for theory, policy or practice Morphology intervention benefits multilingual adolescents by promoting vocabulary knowledge and morphological analysis skill. Improvements in multidimensional vocabulary knowledge and morphological analysis may contribute to supporting reading comprehension.
All Science Journal Classification (ASJC) codes
- Developmental and Educational Psychology
- Psychology (miscellaneous)