Design and reliability of an optometric isiZulu paediatric rate of reading test: A case study

Background: IsiZulu is an official language in South Africa and the primary home language (HL) for many South African children. Currently, there are no optometric reading tests specific for isiZulu-speaking children. Aim: This study aimed to develop and evaluate an isiZulu Paediatric Rate of Reading (PRR) Test for children, with or without visual impairment. Setting: The study was conducted in primary schools of KwaZulu-Natal, South Africa, focusing on isiZulu-speaking primary school children. Methods: The study followed a mixed-methods design. High-frequency isiZulu words from primary school textbooks were used to create six versions of the PRR Test, matching visual acuities from 1.0M to 4.0M. Reliability was tested on 162 isiZulu-speaking primary school children, conveniently selected from HL and First Additional Language (FAL) schools, whereby two examiners recorded results for reading performance over two sessions, one week apart. Results: Bland-Altman plots indicated strong inter-rater agreement with paired t-tests showing no significant differences (P > 0.05) in inter-rater reading parameters. However, statistical differences (P < 0.05) for inter-session agreement were observed for the majority. Intraclass correlations for reading measures ranged from moderate to excellent (0.848–1.000). Conclusion: The test showed good reliability for reading measures, except that reading error variation was observed. Contribution: This study contributes to the development of an isiZulu PRR Test, which is a reliable and linguistically relevant tool for assessing reading abilities in isiZulu-speaking children.