Socioeconomic inequalities and two-year-old children’s language and motor development

In France, where the age for starting mandatory formal schooling has recently been changed from 6 to 3 in the aim of reducing social inequalities from a very young age, INED researchers have been studying children’s language and motor development at age 2, before they start nursery school. Differences by parents’ socioeconomic milieu may be observed from the child’s earliest years. Though physical and language development are closely related, socioeconomic inequalities are particularly important where language is concerned. The vocabulary of children in childcare centers (crèches) or cared for by an outside child-minder is more diverse than the vocabulary of children cared for by their parents or grandparents.

Early childhood is a key phase in brain development and learning, a phase that not only affects their growth but also shapes their cognitive, social, and emotional development. It is a time when they are particularly sensitive to family surroundings and therefore to the variables that influence them, such as parents’ level of education, economic resources, status, possible migrant origins; household composition; and the entire immediate family circle.

What magnitude and impact do socioeconomic inequalities have at this age? Do those inequalities have equally marked effects on children’s language development and motor development? Are there differences by child care situation (cared for by parents or grandparents, collective daycare outside the home)?

In their study, researchers Sébastien Grobon (INSEE/INED), Lidia Panico (INED) and Anne Solaz (INED) used data collected from parents in the framework of the Étude Longitudinal Française depuis l’Enfance or ELFE study (French Longitudinal Study of Children)*. Socioeconomic variables were collected when the children were 1 year old; child development indicators at around 2 years of age (language development indicators for 11,496 children; motor development indicators for 10,740 children).

Inequalities observed in language acquisition but not motor development

Whereas 2-year-olds know, on average, about 74 of the 100 words presented to them, children whose mothers have less than a middle school certificate know 4 fewer words than that, and children whose mothers have completed more than two years’ post-high school education know 6 more.

Children’s language development also differs by childcare situation. Children who go to collective day care or to a licensed child minder have richer vocabularies than children cared for by parents or grandparents, though we cannot conclude that this difference is due to the childcare situation. Going to outside formal childcare tends to reduce socially related inequalities in language development. Being in contact with professional childcare personnel who give children educational activities adapted to their age can work to enrich their vocabulary.

With regard to motor development at age 2, children in the sample could do, on average, 6.5 of the 8 motor activities that parents were questioned about. While a vast majority of children performed at least 3 activities, the activities were not all the same, and few children were able to perform all 8; specifically, 10% of children aged 23 months could do so, and 20% of those aged 28 months. Parents’ level of education and income do not have much influence here. However, the motor development of children whose mothers have completed over two years of post-high school education is slightly below those of children whose mothers have only a high school diploma. Little difference in motor development by childcare mode was found. Being in public collective daycare does seem to lead to slightly greater motor development than the other situations.

The language and motor development indicators used

Socioeconomic inequalities in child development were analysed using indicators. To assess language acquisition, we used the MacArthur-Bates inventory, which measures extent and variety of acquired vocabulary by measuring the number of words spontaneously uttered by the child from among a list of 100. The motor development indicator combines 8 criteria involved in ability to perform different activities, including climbing stairs, hitting a ball, running, pedalling on a tricycle, eating unassisted, drinking unassisted, putting on shoes or socks unassisted, and walking unassisted by 18 months—an age that corresponds to the limit considered normal by the World Health Organisation. This indicator thus covers both overall motor function and fine motor skill.

Multiple causes implicated in the differences

The study is descriptive and so does not reach precise conclusions on the origins of the observed inequalities. However, it does put forward points to explore, noting, for example, that a very small proportion of gaps are related to the socio-demographic characteristics of sibling group size, child’s health at birth, parents’ migration status, or parents’ age. Above all, it suggests that collective childcare is beneficial, particularly for cognitive development, and particularly for children from disadvantaged families. With other characteristics controlled for, children in a crèche or cared for by an outside licensed child-minder seem to have acquired a richer vocabulary than children cared for by parents or grandparents.

Source : Grobon S, Panico L, Solaz A. Inégalités socioéconomiques dans le développement langagier et moteur des enfants à 2 ans. Bull Epidémiol Hebd. 2019;(1):2-9.

Contact: Anne Solaz

Online: March 2019