Exploring the impacts of linguistics, working memory, age, and gender on the quantity-number competencies model.

• All the involved linguistic skills had effects on QNC Levels I and III, whereas only vocabulary yielded support for QNC Level II. • Working memory may bear domain-general nature in their contributions to various QNC levels. • The effect of QNC Level IIa on QNC Level III increased significantly with age. • The impact of QNC Level I on QNC Level IIb increased as the proportion of girls increased in the sample. This meta-analysis systematically investigated the pathways to the Quantity-Number Competencies (QNC) model based on 78 studies involving 21,860 children. The QNC model assumes children acquire early numeracy via three developmental levels: QNC Level I (Basic numerical skills), QNC Level IIa (imprecise quantity to number-word linkage) and QNC Level IIb (precise quantity to number-word linkage), and QNC Level III (relations between numerical quantities). Findings showed (1) all the involved linguistic skills had effects on QNC Levels I and III, whereas only vocabulary yielded support for QNC Level II; (2) phonological and visuospatial working memory made comparable contributions to all QNC levels; (3) most paths within QNC stayed stable with development, with the path coefficient from QNC Level IIa to QNC Level III increased significantly with age; and (4) the path coefficient from QNC Level I to QNC Level IIb increased as the proportion of girls increased in the sample. These findings suggest the phonological awareness might primarily support representations for number words and number facts, whereas vocabulary might facilitate the linkage between number words and quantities. The similar effects of different working memory on QNC levels suggested working memory's general storage and processing abilities underlie early numeracy development. [ABSTRACT FROM AUTHOR]