Vocabulary Development in European Portuguese: A Replication Study Using the Language Development Survey

Area of Science:

• Developmental Psychology
• Linguistics
• Child Language Acquisition

Background:

• Cross-linguistic studies are crucial for understanding universal and language-specific aspects of child language development.
• Previous research using the Language Development Survey (LDS) has explored vocabulary acquisition in various languages.
• Understanding factors influencing early vocabulary size and composition is key for identifying developmental trajectories.

Purpose of the Study:

• To replicate cross-linguistic findings on vocabulary development in Portuguese and U.S. children.
• To examine the effects of language, gender, and age on vocabulary size and lexical composition.
• To investigate characteristics of late talking in these populations.

Main Methods:

• Utilized the Language Development Survey (LDS) with European Portuguese (n=181) and English (n=206) speaking children aged 18-35 months.
• Compared vocabulary scores, lexical composition, and identified late talkers (children ≥ 24 months with < 50 words).
• Analyzed cross-linguistic concordance of word usage and vocabulary composition.

Main Results:

• Girls exhibited higher vocabulary scores than boys; scores increased with age in both language groups.
• Portuguese children had lower LDS scores than English-speaking children, with a small effect size.
• High cross-linguistic concordance was observed in word usage (Q correlation = .50) and vocabulary composition, particularly in younger children.

Conclusions:

• Findings replicate previous LDS studies in Greek, Korean, and Italian, supporting universality in early lexicons.
• Early lexicons of typical and late talkers share many common words, suggesting shared developmental pathways.
• The universality of early word use provides potential targets for clinical interventions in language development.