Debbie Mills

Vocabulary of 2-Year-Olds Learning English and an Additional Language: Norms and Effects of Linguistic Distance

Typically-developing bilingual children usually underperform relative to monolingual norms when assessed in one language only. We measured vocabulary with Communicative Development Inventories for 372 24-month-old toddlers learning British English and one Additional Language out of a diverse set of 13 (Bengali, Cantonese, Dutch, French, German, Greek, Hindi-Urdu, Italian, Mandarin, Polish, Portuguese, Spanish and Welsh). We furthered theoretical understanding of bilingual development by showing, for the first time, that linguistic distance between the child’s two languages predicts vocabulary outcome, with phonological overlap related to expressive vocabulary, and word order typology and morphological complexity related to receptive vocabulary, in the Additional Language. Our study also has crucial clinical implications: we have developed the first bilingual norms for expressive and receptive vocabulary for 24-month-olds learning British English and an Additional Language. These norms were derived from factors identified as uniquely predicting CDI vocabulary measures: the relative amount of English versus the Additional Language in child-directed input and parental overheard speech, and infant gender. The resulting UKBTAT tool was able to accurately predict the English vocabulary of an additional group of 58 bilinguals learning an Additional Language outside our target range. This offers a pragmatic method for the assessment of children in the majority language when no tool exists in the Additional Language.

IV: RESULTS FOR STUDIES 2 AND 3: THE UKBTAT MODEL AND ITS APPLICATION TO NONTARGET ADDITIONAL LANGUAGE LEARNERS: STUDIES 2 AND 3: CHARACTERISTICS OF THE UKBTAT

This article is part of the issue “Vocabulary of 2-Year-Olds Learning English and an Additional Language: Norms and Effects of Linguistic Distance” Floccia, Sambrook, Delle Luche, Kwok, Goslin, White, Cattani, Sullivan, Abbot-Smith, Krott, Mills, Rowland, Gervain, and Plunkett (Issue Authors). For a full listing of articles in this issue, see: http://onlinelibrary.wiley.com/doi/10.1111/mono.v83.1/issuetoc.

V: GENERAL DISCUSSION.

This article is part of the issue “Vocabulary of 2-Year-Olds Learning English and an Additional Language: Norms and Effects of Linguistic Distance” Floccia, Sambrook, Delle Luche, Kwok, Goslin, White, Cattani, Sullivan, Abbot-Smith, Krott, Mills, Rowland, Gervain, and Plunkett (Issue Authors). For a full listing of articles in this issue, see: http://onlinelibrary.wiley.com/doi/10.1111/mono.v83.1/issuetoc.

Vocabulary of 2-year-olds learning English and an additional language: norms and effects of linguistic distance. II: METHODS

T HE PROCEDURE and methods used in the initial examinations of all cohorts have been described in detail (Keys et al., 1967, pp. 24-54). Except for additional items in the protocol, noted below, the same procedures and methods were used in the reexaminations five years later, and with few exceptions the same professional and assisting staff conducted the work both times. On the second as on the first occasion, the great majority of the examinations were made in the mornings before the men had indulged in any strenuous work although most of them had eaten their usual breakfast before reporting for examination. The sequence of events in the examinations started with registration by an assistant, native to or at least greatly familiar with the area and its population, who recorded any changes in family and occupational status and in personal habits, including smoking. That assistant, usually a nurse or medical technician but sometimes a physician, filled out the London School of Hygiene Cardiovascular Questionnaire (see Rose and Blackburn 1968, Annex 6). After disrobing to underwear and socks, measurements of height, weight, and thickness of the skinfolds over the triceps muscle and over the tip of the scapula were made with the same standardized methods as used in the entry examinations. Respiratory function tests, which will not be reported here, preceded the medical history and physical examinations, two internists taking alternate subjects for this latter purpose. Blood pressure was recorded at least twice at that stage. The forms for initial data, medical history, and physical examination are reproduced in the Appendix of this report. The 12-lead electrocardiogram was recorded in supine rest on multichannel machines, with routine control of calibration and paper speed (25 mm/sec). Except where there was manifest heart disease or other contraindication, a three-minute exercise test was made with repetition of the ECG