Morphological awareness and vocabulary knowledge in monolingual and bilingual learners: A meta-analysis

Aims: This meta-analysis aimed to quantify the overall within- and cross-linguistic relationships between morphological awareness (MA) and vocabulary knowledge and identify moderators that influence their associations in monolingual and bilingual learners. Methodology: We conducted a meta-analysis using 109 primary studies that met our inclusion criteria. Data from 79 L1 studies (involving 14,172 monolingual learners) and 30 L2 studies (involving 4,288 bilingual learners) were extracted. Data and analysis: Studies were coded for learner characteristics, such as age, language background, and L1–L2 distance, as well as assessment characteristics, including task modality (e.g., oral vs. written), task content (e.g., derivation and compound), and response type (production vs. reception). Findings/conclusions: The results indicated that (a) in monolingual research, there was a moderate correlation between MA and vocabulary (r = .43); (b) in bilingual research, there was a significant positive correlation between L1 and L2 MA (r = .33), and between L1 MA and L2 vocabulary (r = .26); (c) the magnitude of the association between MA and vocabulary increased with age in monolingual learners, while that of the correlation between L1 and L2 MA decreased with age in bilingual learners; and (d) significant variations were observed depending on the specificity of the language(s) involved, as well as several assessment-related moderators. Originality: This study contributes to the existing literature by systematically exploring the degree of association between MA and vocabulary within and across languages and examining whether these associations are influenced by learner and assessment characteristics. Significance/implications: Our results support MA as a multidimensional, transferrable construct and underscore its important role in vocabulary for monolingual and bilingual learners. Several key considerations are discussed for the selection of MA and vocabulary assessment methods.