Measuring word-final consonant clusters in developmental child speech.

The correlation between the measure for cluster proximity (MCP) and the percentage of consonants correct (PCC) for word-initial two-member consonant clusters was recently found in the literature to be strong and statistically significant in developmental child speech. Because of this, MCP norms that quantitatively define stages in cluster development (omission, reduction, vowel epenthesis, and two-member production with a distinction on member accuracy) can be predicted from PCC norms that only measure cluster-member accuracy. In the present study, this investigation is extended to word-final two-member clusters for the purpose of examining whether the correlation between MCP and PCC is also strong and statistically significant as well as comparing stage performance between word-initial and word-final clusters using the MCP measure. The study employs 31 speech samples from 18 children, 16 in atypical and 2 in typical development. The results show that the correlation between MCP and PCC for word-final clusters is as strong and as statistically significant as for word-initial clusters. Furthermore, the correlation between word-initial and word-final MCP is also positive, but somewhat weak. Nevertheless, it indicates that word-final clusters as a whole may be developing earlier than word-initial clusters.