Development and evaluation of the Ingwavuma receptive vocabulary test: A tool for assessing receptive vocabulary in isiZulu-speaking preschool children.

Background: This study used local resources- community members, photographer and speech therapists to develop a new test for screening receptive language skills and sought to determine its feasibility for use with a larger population in KwaZulu-Natal province, South Africa.

Objectives: The aim of this study was to develop a one-word receptive vocabulary test appropriate for screening and diagnosis of isiZulu-speaking preschool-aged children. The objectives were (1) to determine sensitivity and specificity of the Ingwavuma Receptive Vocabulary Test (IRVT) and (2) to determine the relationship of IRVT scores with age, gender, time and the confounding variables of stunting and school.

Method: The study was quantitative, cross-sectional and descriptive in nature. The IRVT was piloted before being administered to 51 children (4-6 years old). Statistical analysis of test item prevalence, correlations to confounding variables and validity measurements were conducted using Statistical Package for Social Scientists version 25 (SPSS 25).

Results: The IRVT was able to profile the receptive skills for the preschool children in Ingwavuma. The mean raw score for boys was 35, and 32 for girls. There was a significant Pearson correlation between test scores and age (0.028, p 0.05) with a high effect size (Cohen's d = 0. 949), gender (r = -0.032, p 0.05) with a medium effect size (Cohen's d = 0.521) and school (r = 0.033, p 0.05) with a small effect size (Cohen's d = 0.353). The sensitivity and specificity values were 66.7% and 33%, respectively. The test reliability (Cronbach's alpha) was 0.739, with a good test-retest reliability.

Conclusion: The IRVT has potential as a screening test for isiZulu receptive vocabulary skills amongst preschool children. This study contributes to a development of clinical and research resources for assessing language abilities.