JCPSLP Vol 14 No 2 2012

Analysis and results The analyses were conducted using the Child Language Analysis (CLAN, MacWhinney, 2009) program. The total number of words (TNW) and total number of different words (TNDW) are presented in Table 1. As shown in Table 1, the vocabulary used in the written samples was more diverse (type token ratio; TTR = 0.10), than that used in the spoken samples (TTR = 0.06). In both datasets, the most frequently occurring words accounted for a large proportion of the total words produced. As shown in Table 2, the proportions accounted for by the most frequently occurring 10, 50, and 100 words were very similar across the two datasets. Table 1. Summary statistics for written and spoken samples Measure Written samples Spoken samples Total number of words 27,643 109,710 Total number of words / 23 508 number of samples Total number of different 2799 6052 words Type token ratio (TTR) 0.10 0.06 Note: TTR = Total number of words / Total number of words Table 2. Proportion of total words represented by most frequently occurring 10, 50, and 100 words Word list Proportion of total number of words Written samples Spoken samples Tables 3, 4, and 5 outline the 20 most frequently occurring words, 2-word sequences, and 3-word sequences. The words marked with an asterisk occurred in the ‘Top 20’ lists for both written and spoken datasets. Eight of the Top 10 words were the same across datasets. These words were: I, and, the, to, a, my, it, and we . These were all structure words (pronouns, articles, conjunctions, prepositions) as opposed to content words (nouns, verbs, Table 3. Twenty most frequently occurring words Written samples Spoken samples 1. I* 11. on* 1. and* 11. you 2. and* 12. was* 2. the* 12. got 3. the* 13. am 3. I* 13. that 4. to* 14. went 4. a* 14. one 5. a* 15. are 5. to* 15. then 6. my* 16. in* 6. it* 16. of 7. is 17. she 7. my* 17. he 8. it* 18. have 8. we* 18. because 9. we* 19. me 9. in* 19. was* 10. going 20. like 10. on* 20. yeah Note. * Word occurred in Top 20 for both spoken and written modalities. The Top 100 Word List can be obtained by contacting the first author. Most frequently occurring 10 words Most frequently occurring 50 words Most frequently occurring 27% 32% 52% 56% 64% 66% 100 words

adverbs, adjectives). Eleven of the Top 20 words, and 64 of the Top 100 words were the same across the two modalities. Differences were found across the two datasets with words like yeah and just ranking much higher in the spoken samples than the written, and words like today and birthday ranking higher in the written samples than the spoken. The 2- and 3-word sequences also revealed differences with sequences like I am going and I went to ranking higher in the written samples than the spoken, and sequences like I don’t know and And that’s all ranking higher in the spoken samples than the written. Age-comparisons using the Top 100 word lists for the two modalities revealed that the overlap was greatest for the 5-year-old children with 42 words shared across both word lists. The overlap for the 6-year-old children was 34 words, and for the 7-year-old children it was 33 words. Implications and future directions This study highlighted the similarities and differences in spoken and written vocabulary use in typically developing NZ children. The word lists generated can be used to support the face-to-face and written communication development of NZ children who use AAC. These word lists are particularly relevant for children in the first three years of formal schooling as it is likely that the vocabulary used 10. going to have 20. in the weekend 10. and it was* 20. when I was Note. *Three-word sequence occurred in Top 20 for both spoken and written modalities Table 4. Twenty most frequently occurring 2-word sequences Written samples Spoken samples 1. going to 11. in the* 1. and then 11. don’t know 2. I am 12. it is 2. and I* 12. and it 3. and I* 13. she is 3. on the* 13. to the* 4. went to 14. are going 4. and we* 14. and he 5. I went 15. I got 5. in the* 15. and you 6. am going 16. on the* 6. and my* 16. my mum 7. to the* 17. I have 7. I don’t 17. have to 8. it was* 18. and she 8. and the 18. go to 9. we are 19. and we* 9. it was* 19. and they 10. I like* 20. and my* 10. got a 20. I like* Note. * Two-word sequence occurred in Top 20 for both spoken and written modalities. Table 5. Twenty most frequently occurring 3-word sequences Written samples Spoken samples 1. I am going 11. going to the 1. I don’t know 11. and my mum 2. am going to 12. I have a 2. and then we 12. and my dad 3. I went to 13. and I got* 3. you have to 13. go to the 4. are going to 14. and it was* 4. and then I 14. and then he 5. we are going 15. and we are 5. we had to 15. play with my 6. went to the 16. going to play 6. and that’s all 16. and we had 7. is going to 17. I had a 7. and I got* 17. play on the 8. and she is 18. it was fun 8. and then you18. to go to 9. I got a 19. and I am 9. we went to 19. I’ve got a

70

JCPSLP Volume 14, Number 2 2012

Journal of Clinical Practice in Speech-Language Pathology