Development and evaluation of the Ghanaian digit triplet test for adult hearing screening.

Objectives: This study aimed to develop and evaluate a Ghanaian Digit Triplet Test for adult hearing screening.

Design: The study was conducted in two phases. Phase 1 optimised digit recognition across speech materials in a controlled environment, while Phase 2 collected normative data and assessed list equivalence using an adaptive and fixed-level method.

Study sample: Eighty adults aged 18 to 50 years with normal hearing thresholds (≤ 15 dB HL) participated: 16 in Phase 1 and 64 in Phase 2.

Results: The mean SRTs were -11.3 dB for Asante-Twi and -11.4 dB for Ghanaian English, closely matching other digit triplet tests. Psychometric slopes were 17.9%/dB for Asante-Twi and 19.4%/dB for Ghanaian English. No significant differences were found in SRTs across list numbers or orders for the Asante-Twi version, indicating list equivalence and no learning effect. However, a significant learning effect in the Ghanaian English version necessitated different normative values based on participants' test exposure.

Conclusions: The GDTT demonstrates consistency with other digit triplet tests while addressing specific linguistic and cultural factors. The test can improve access to hearing screening in resource-limited settings in Ghana. Further research should explore the test's applicability to a broader demographic, including children.