Do developmental milestones at 4, 8, 12 and 24 months predict IQ at 5-6 years old? Results of the EDEN mother-child cohort

Eur J Paediatr Neurol. 2017 Mar;21(2):272-279. doi: 10.1016/j.ejpn.2016.11.001. Epub 2016 Nov 15.


Rationale: The present study aims: (i) to determine how well developmental milestones at 4, 8, 12 and 24 months may predict IQ at 5-6 years old, (ii) to identify cognitive domains during the first two years that best predict later IQ and (iii) to determine whether children with IQ in the normal range at 5-6 years old may differ from disabled (IQ < 70) and gifted children (IQ > 130) with regard to their early cognitive development.

Method: The main developmental milestones were collected through self-administered questionnaires rated by parents at 4, 8, 12 and 24 months and through parental questionnaires administered by a trained interviewer and questionnaires completed following a medical examination at 12 months. These questionnaires were derived from the Brunet-Lézine Psychomotor Development Scale and they addressed several cognitive domains (gross and fine motor skills, language and socialization).

Results: (i) Developmental milestones predict a substantial part of the later IQ variance from 24 months (R2 ∼ 20%). (ii) Early language skills more strongly predict later IQ than the other cognitive domains. (iii) Several cognitive domains, but particularly language skills, predict disabled children at 5-6 years old (from the age of 8 months) and gifted children (from the age of 12 months).

Discussion: The present study provides valuable information for early developmental assessment and could contribute to a better understanding of intellectual development.

Keywords: Cognitive development; Developmental milestones; Giftedness; IQ; Intellectual disability; Intelligence.

MeSH terms

  • Aging / psychology
  • Child
  • Child Development*
  • Child, Gifted / psychology*
  • Child, Preschool
  • Cohort Studies
  • Disabled Children / psychology*
  • Female
  • Humans
  • Infant
  • Intelligence Tests*
  • Intelligence*
  • Male
  • Parents
  • Reference Values
  • Surveys and Questionnaires