Comparison of PMLU in Kannada Speaking Down's Syndrome and Typically Developing Children

Abstract

Phonological Mean Length of Utterance, (PMLU) is a whole word measure for determining phonological proficiency and is one of the new tools for quantifying development of word forms in both normal and clinical population. Even though PMLU measures phonological proficiency, its utility in clinical populations like Down's syndrome is not clearly understood. Since there is a scarcity of information on PMLU measures, the present study focuses on comparing PMLU scores in Kannada speaking Down's syndrome and language age matched normal children. Two groups of Kannada speaking children were included in the study: Group1 composed of normal children (n = 60 and chronological age of 3-4 years) matching the language age of group 2. Group 2 comprised of children with Down's syndrome (n = 35 and chronological age of 6-15 years) with mild to moderate mental retardation and expressive language age of 3-4 years. Picture naming task using Kannada Articulation test was done and 25 words were randomly selected for PMLU analysis. Samples were recorded using digital professional voice recorder and the children's utterances were calculated for PMLU measures. Obtained scores were analysed using SPSS 16.0 version by Independent t- test with p value kept at 0.05. The results revealed statistically significant difference in PMLU scores between Down's syndrome population and typically developing children. These reduced scores are indicative of poor whole word complexity in children with Down's syndrome. Findings of the study indicate that PMLU measure could be a benchmark in assessing the phonological skills in disordered population.