Reliability and Associations of English and Mandarin Vocabulary Measures in Infants and Toddlers Growing Up in a Multilingual Society

This paper aims to understand the reliability of English and Mandarin vocabulary measures, and their associations, among infants and toddlers growing up in a multilingual society. Reliability was examined via item-response Rasch models across English and Mandarin word categories. Parents reported on 137 children’s (age = 5 to 27 months) English and Mandarin vocabulary with a newly developed measure, the developmental vocabulary checklist (DVC). High reliability (alpha .91 to .99) was observed across English and Mandarin DVC categories. Wright maps suggest a lack of sensitivity at the tail end of the language-ability distribution. One-way ANOVAs indicating a significant difference across expected categories of DVC words was found. Higher exposure associated with a higher composite score across DVC categories, but only in Mandarin and only among older children in the 1-to-2 year band. A threshold account is discussed as an explanation for differential association of exposure in Mandarin but not English.