DOI: 10.5255/ukda-sn-856987
title: Quantifying Language Experience in Bilingual and Trilingual children, 2020-2022

description: The data in this repository were collected in France, the Netherlands and the UK between 2020 and 2022 to inform the validation of the Q-BEx questionnaire (). Children between the ages of 5 and 9 were tested individually to assess their proficiency in the societal language (i.e., French, Dutch or English), as well as their non-verbal intelligence and working memory. One of their parents or caregivers also filled in the full version of the Q-BEx questionnaire. The respository includes data from 299 children (FR: n=78, NL: n=117, UK: n=104), although some measures are not available for all children.
In France, children were recruited in ordinary schools and in private clinics for Speech & Language Therapy (37 children were recruited via clinics). The consent form for schools asked parents if the child had previous or current SLT, and the reason. In the Netherlands, recruitment took place in schools and via social media advertisement. Language disorder (reported by parent/teacher/remedial teacher) was an exclusionary criterion. In the UK, all children were recruited in schools; no exclusionary criteria were applied, and not SLT information was collected.
Language experience data*
Language experience data was collected using the full version of the Q-BEx questionnaire (), which was completed by one of the child’s parents or caregivers. This includes all the following modules (except that Language mixing wasn’t included in France):
- Background (languages the child is exposed to, adults and children the child lives with
- Risk factors (early language milestones, early parental concerns)
- Language exposure and use (current and cumulative estimates; onset of exposure to each language)
- Estimates of proficiency in each language (listening, speaking, reading, writing)
- Richness of experience in each language (activities, diversity of interlocutors, parental education)
- Language mixing
- Attitudes
The questionnaire was administered either in the societal language (French, Dutch or English) or in one of the child’s home languages (Arabic, Dutch, English, French, German, Italian, Polish, Romanian, Russian, Spanish, Turkish). The choice of administration language was constrained by the translated versions available at the time of testing. The translation protocol used to create the versions in different languages can be found at .
Direct outcome measures
We collected measures of language and cognitive outcomes during individual, face-to-face sessions with each child (two sessions per child, lasting approximatively 45 minutes each). Most of the testing was done in the child’s school. In France, the children recruited via speech & language therapy clinics were tested in the clinic. In the UK and the NL, some testing sessions took place in a different location (e.g., university premises), and on rare occasions online via Zoom.
Language proficiency
Outcomes in the societal language (i.e., Dutch, English, or French) include phonology, morphosyntax and vocabulary.
Phonology
Phonological competence was assessed with the LITMUS Quasi-Universal Non-Word Repetition task. See dos Santos, C., and Ferré, S. (2016) “A Nonword Repetition Task to Assess Bilingual Children’s Phonology”. Language Acquisition 41: 1–14.
Morphosyntax
Morphosyntax outcomes were assessed with the LITMUS test in each societal language. See Marinis, T. and S. Armon-Lotem (2015). “Sentence Repetition. Methods for assessing multilingual children: disentangling bilingualism from Language Impairment.” in S. Armon-Lotem, J. de Jong and N. Meir, Methods for assessing multilingual children: disentangling bilingualism from Language Impairment. Amsterdam: Multilingual Matters).
The English and Dutch versions included 30 items. The French version included 16 items. We created two blocks in the English and Dutch versions so that the first block be comparable to the 16-item French version. Subsequent analyses demonstrated that there was no block effect in EN and NL.
For each child, we report three overall scores: Identical Repetitions, Target Repetitions, and Grammatical Attempts. These overall scores correspond to the mean across items (n=30 in English and Dutch; n=16 in French), excluding NAs (i.e., the mean is calculated on the items for which the child did provide a response).
Vocabulary
Vocabulary breadth was measured in the UK with the British Picture Vocabulary Scale (BPVS), in France with the the Échelle de vocabulaire en images Peabody (EVIP), and in the Netherlands with the Peabody Picture Vocabulary Test (PPVT).
Vocabulary depth was measured with the Word Classes component of the Clinical Evaluation of Language Fundamentals CELF-V (in its Dutch, English, or French version).
Cognitive measures
The tasks used to evaluate cognitive skills were administered in the child’s societal language.
Memory
Short-term memory was assessed through Forward Digit Recall; working memory was assessed through Backward Digit Recall.
Most children were tested using the digit span protocols described in Hill et al (2021), implemented in Psychopy (to allow randomisation of the digit sequences and facilitate the acquisition of detailed data). Children were presented with sequences of numbers (through headphones) and asked to repeat these numbers either in the same order (in the FDR task) or in reverse order (in the BDR task). The length of the sequence increased by one digit after 4 trials, starting with 3 digits in the first block of the FDR task, and 2 digits in the first block of the BDR task. The maximum sequence length was 6 digits in the FDR task, and 5 digits in the BDR task.

Children recruited via the Speech and Language Therapy clinics in France (n=37) experienced more difficulty with this task, so it was decided to use the WISC-V protocol instead for these children, as it included a discontinuation rule.

To allow comparison across groups, we created a WISC-like score for the data collected via the Hill et al (2021) protocol. This consisted in the digit span for which the child had at least one fully accurate response (i.e., all the digits in the span, in the right order) for at least one out of the first two trials for that span (as the WISC-V protocol only features 2 trials per digit span).

FDR_overall and BDR_overall correspond to the total accuracy scores, as per the Hill et al (2021) protocol.
FDS_Q and BDS_Q correspond to either the WISC-V score (for children recruited via clinics) or the WISC-like score created as explained above, depending on which protocol the child was tested with. All children have a FDR_Q and a BDR_Q score in the dataset.

Non-verbal intelligence
The matrices task from either the Wechsler Intelligence Scale for Children–Fifth Edition (WISC–V) or the Wechsler Preschool & Primary Scale of Intelligence - Fourth UK Edition (WPPSI-IV) was used to measure non-verbal intelligence - depending on the age of the child: children below the age of 6 were tested with the WPPSI.

Depending on the age of the child at the time of testing, we used the WPPSI protocol (for children younger than 6 years of age, n= 77) or the WISC-V protocol (for all the other children).