Language Variations in Standardised Assessments: Evidence From Indonesia

Assessment of young children’s language skills is essential for monitoring development and informing early intervention. However, widely used assessment instruments are often developed for monolingual English-speaking contexts and may not align with children’s linguistic environments in multilingual settings. This feasibility study examined the adaptation of the Bayley-4 Language Scale (Bayley & Aylward, 2019) for Indonesian–Sasak toddlers using an iterative framework integrating linguistic, cultural, and psychometric evaluation. Rasch modelling supported the internal coherence of both receptive and expressive communication subtests while identifying a small number of statistically misfitting items. Subsequent linguistic and cultural analyses indicated that these items were often associated with English-specific grammatical constructions, culturally unfamiliar visual stimuli, or variability in caregiver-reported behaviours. Item-level analyses further showed how language variation between Indonesian and Sasak, together with local communicative routines, shaped response patterns and developmental ordering. These findings highlight the importance of evaluating item feasibility when adapting standardised language assessments to bilingual contexts. Building on this analysis, the study proposes an iterative, feasibility-based adaptation framework that integrates linguistic analysis, cultural review, and psychometric evidence to guide context-sensitive assessment refinement in bilingual settings, with broader methodological relevance for future work in multilingual environments.