Table 2: Mean ages obtained for oral and written language development in a sample of “high-potential” French children in the course of the first three years of life compared to Brunet-Lézine norms.

Mean age obtained on items observed (Vaivre-Douret) [5]Reference Brunet-Lézine EAP 1951 revised [9]

Babbling (consonants): mean 4 months + 3 weeks.7 months8 months
First words (at least three): mean 9 months + 1 week.12 months10–17 months
Repetition of words in exponential manner from 12 months ± 4 weeks18 months17 months
First phrase (association of two words): mean 18 months ± 2 weeks21 months20 months
Imitation animal noises: mean 22 months ± 2 weeks
Accurate vocabulary, no baby talk language mature, easy, correct use of verb tenses: mean 22 months ± 2 weeks
Early spontaneous identifications letters and figures in the environment: mean 24 months ± 4 weeks
Enjoys giving synonyms or opposites: mean 28 months ± 4 weeks
Uses “I” (first person pronoun): mean 30 months ± 2 weeks30 months30 months
“Pretend” writing: mean 34 months ± 2 week

(—) No data from authors.