BSL Communicative Development Inventory

What is it?

This is a developmental checklist of signs used and understood by babies and infants aged 8-36 months. It is easy to complete online and provides a snapshot of a child’s sign vocabulary in BSL.

What is involved?

This is a parent checklist that takes about 45 mins to complete. It is completed by parents on the computer – following the instructions of a practitioner or researcher who has experience of working with young deaf children.

Who is it suitable for?

  • Deaf or hard of hearing babies and infants aged 8 - 36 months who are learning BSL
  • It is not designed to measure sign language development in older children or adults with learning disabilities or those who use Makaton.

What normative data is available?

Deaf children aged 8 - 36 months

Who should use this test?

  • Early educators may use the test to assess a child's sign language development and check progress. If a child is not making good progress, the test can pinpoint areas of sign language for teachers to target.
  • Practitioners e.g. Speech and language therapists or those providing early years intervention
  • Parents who want to know if their child's BSL vocabulary is on track for their age
  • Researchers
  • Lecturers for demonstration purposes

Insert sample report

Test citation and norms

Woolfe, T., Herman, R., Roy, P., & Woll, B. (2010). Early vocabulary development in deaf native signers: a British Sign Language adaptation of the communicative development inventories. Journal of Child Psychology and Psychiatry, 51(3), 322-331.



Data is generated in CSV format for easy import into your preferred data management software

Task data

A separate CSV file is generated for each participant. Each contains the raw data including the order of items on the checklist, a Comprehension score of Yes (1) or No (0) for each item, and a Production score of Yes (1) or No (0) for each item.

Accuracy data

One mark is awarded for each item scored as understood and one mark for each item scored as signed. The overall maximum score for Comprehension (“Understands”) on the CDI is 572. This consists of 551 single signs and 21 sign phrases. The overall maximum score for Production (“Signs”) is 572. This also consists of 551 single signs and 21 sign phrases.

For questions related to this test, please contact the task owner, Bencie Woll