The UK C-BiLLT: Validity and reliability of an online assessment of spoken language comprehension for children with severe motor disorders

Background

Current UK measures of early spoken language comprehension require manipulation of toys and/or verbal responses and are not accessible to children with severe motor impairments. The Computer-Based Instrument for Low motor Language Testing (C-BiLLT) (originally validated in Dutch) is a computerized test of spoken language comprehension that children with motor disorders control using their usual response methods.

Aims

To create a UK version of the C-BiLLT, evaluate its validity and reliability, and assess its practicability for children with motor disorders.

Methods & Procedures

The C-BiLLT was translated into British English and items were adapted to ensure familiarity to UK children. A total of 424 children (233 females, 191 males) aged 1:6–7:5 (years:months) without developmental disabilities were recruited from North East England. Children completed the UK C-BiLLT and Preschool Language Scales 5 (PLS-5) for convergent validity evaluation and either the visual reception subtest of the Mullen Scales of Early Learning (MSEL) (children aged 1:8–5:5) or Ravens Coloured Progressive Matrices (CPM) (ages 5:6–7:5) to assess divergent validity. A total of 33 children completed the UK C-BiLLT within 4 weeks of initial assessment for test–retest reliability assessment (intraclass correlation coefficient—ICC). Internal consistency was assessed using Cronbach's alpha and exploratory factor analysis examined structural validity. A total of 24 children (10 female, 14 male; aged 4–12 years) with non-progressive motor disorders who use augmentative and alternative communication (AAC), rated the UK C-BiLLT's ease of use and completed British Picture Vocabulary Scales (BPVS) and CPM as for convergent and divergent validity testing.

Outcomes & Results

Internal consistency was high for children without motor disorders (α = 0.96). Exploratory factor analysis extracted two factors, together explaining 68% of the total variance. Test–retest reliability was excellent (ICC = 0.95; 0.90–0.98 95% confidence interval—CI). UK C-BiLLT scores correlated highly with PLS-5 (r = 0.91) and MSEL (r = 0.81), and moderately with CPM (r = 0.41); and increased across full-year age-bands (F(6, 407) = 341.76, p = < 0.001, η² = 0.83). A total of 19 children with motor disorders rated the UK C-BiLLT as easy/ok to use; two judged it hard; three declined to rate the ease of use. Their UK C-BiLLT scores correlated highly with BPVS (r = 0.77) and moderately with CPM (r = 0.57).

Conclusions & Implications

The UK C-BiLLT is a valid, reliable measure of early spoken language development and is potentially practicable for children with motor disorders. It may facilitate international research on the language development of children with motor disorders and evaluation of intervention at the national level.

WHAT THIS PAPER ADDS

What is already known on the subject

• Young children with motor disorders have difficulties accessing standardized assessments of language comprehension that require children to handle objects or to speak a response.

What this paper adds to the existing knowledge

• This study demonstrates the validity and reliability of a UK translation of the C-BiLLT and suggests that the measure is feasible for children with motor disorders who use AAC and have a reliable method of response via computer access.

What are the potential or clinical implications of this work?

• The UK C-BiLLT is a useful addition to the limited tools currently available to assess early spoken language comprehension of children with motor disorders.