Background and Aim: Measures of oral diadochokinesis are widely used in the assessment and detecting motor speech disorders and functional abnormalities of speech performance. Preschoolers have great difficulties with this clinical task. One reason for this problem is application of using of non-words in the test. Since, such words were not designed in Farsi; therefore we compared some words and non-words repetitive articulatory rate in preschool children.

Materials and Methods: In this analytic cross-sectional study design, 142 children (65 boys & 77 girls) aged 4 to 6 years old were participated. We compared timing for 10 fast repetitions between two meaningful words /motækΛ, golΛbi/ and tri-syllabic sequences /pΛtΛkΛ/. Data was analyzed by repeated measures of ANOVA test.

Results: In children aged 4 to 5 years old, mean ± SD of timing for 10 repetitions of /pΛtΛkΛ, motækΛ, golΛbi/ were 7.72±1.02, 6.58±1.68 & 6.65±1.13 seconds respectively, and in children aged 5 to 6 years, were 7.57±0.95, 6.35±1.38 & 6.30±1.01 seconds respectively. This Analysis showed that regardless of all factors, the main effect of type of words on oral diadochokinesis was significant (p=0.0001). There were no other significant main effects or interactions.

Conclusion: Children aged 4 to 6 years old could repeat meaningful words /motækΛ, golΛbi/ faster than non-word /pΛtΛkΛ/. Sex and age group factors had not significant effect on oral diadochokinesis function. Finally, it is suggested that speech therapists can examine this ability with meaningful words.

Keywords: Oral diadochokinesis, Word, Non-word