Determining the core vocabulary used by Sepedi-speaking preschool children during regular preschool-based activities

Abstract

Augmentative and alternative communication (AAC) systems can benefit persons whose speech is too limited to meet their communication needs. Some AAC systems require words and phrases to be preselected and represented on the system, to allow the person using the system to select them for expression. In order to be usable, such AAC systems require the selection of a limited set of words from possibilities. Core vocabulary consists of words from a variety of word classes that appear most frequently in natural conversations. It has been suggested that the inclusion of these words on the AAC system can give people using the system access to the production of many different phrases and sentences, thereby enhancing their expressive power. Since core vocabulary is language-specific, the study’s aim was to determine the core vocabulary of Sepedi-speaking preschoolers, in order to inform the vocabulary selection for AAC systems for children in need of AAC from a Sepedi language background. The speech of six preschool children without disabilities was recorded using small body-worn audio recording devices. Children were recorded during their regular preschool day. The recordings were transcribed, coded and analysed. The composite transcript consisted of 17 579 words, of which 1 023 were different words. The core vocabulary was determined by identifying all words that were used with a minimal frequency of 0.5‰, and that were used by at least half of the participants. The Sepedi core vocabulary consisted of 226 words that accounted for 88.1% of the composite sample. As in other studies, the core vocabulary consisted of a smaller number of words that represent a large proportion of the composite sample. The core word list determined in this study can be used as one resource among others to assist with vocabulary selection for children from a Sepedi language background who may require AAC.