Early child development and its determinants: Findings from a large cohort of healthy children growing up in a low-risk environment.

BACKGROUND: Despite numerous studies on early child development, there is still much to be discovered about the significance of possible risk factors. This study examines cognitive, motor, and language development of healthy children growing up in a low-risk environment and how various individual and environmental factors are associated with it. The study also considers whether the importance of particular parameters changes depending on child age. METHODS: Within the framework of the LIFE Child study in Leipzig, Germany, 481 children participated in a total of 832 visits between 1 and 36 months of age. Developmental status was assessed using the Third Edition of the Bayley Scales of Infant and Toddler Development. Linear regression analyses were applied to examine the associations between child development and sex, gestational age, birth weight, birth mode, overweight, height, and parental education. RESULTS: Mean Bayley composite scores for cognitive, language, and motor development were close to the standard value of 100. Poorer developmental outcomes were significantly associated with lower gestational age, vacuum cup/forceps birth, being overweight, small height, and lower parental education, although some of the associations became insignificant after applying multivariate models. While the association between gestational age and language development became weaker with advancing age, our interaction models found disparities related to parental education to become more apparent in older children across all three domains of early child development. CONCLUSIONS: Several factors were identified to be associated with early child development. As children grow older, obstetric parameters, for example, gestational age, might become less relevant compared with sociodemographic factors, for example, parental education.

Associations between sociodemographic and behavioural parameters and child development depending on age and sex: a cross-sectional analysis.

OBJECTIVES: To explore environmental and individual factors that are associated with child development and to investigate whether the strength of these associations differs according to the age of the children. DESIGN: Cross-sectional study. SETTING: This study was part of the LIFE Child study, a large cohort study conducted in Leipzig, Germany. PARTICIPANTS: 778 children aged between 0.5 and 6 years (48.6% girls, mean age=2.67 years). OUTCOME MEASURES: The outcomes were cognitive development, language development, body and hand motor skills, social-emotional development, and tracing skills, measured with a standardised development test. We analysed the associations between development and gestational age, socioeconomic status (SES), sex, behavioural difficulties, siblings, sleep duration, breastfeeding duration and overweight/obesity. We also tested for interactions between these variables and child age or sex. RESULTS: Higher gestational age (b ranging between 0.12 and 0.26) and higher SES (b ranging between 0.08 and 0.21) were associated with better outcomes in almost all developmental domains (all p<0.019). Children with older siblings had improved body and hand motor skills compared with children without older siblings (both b=0.55, all p<0.029). Boys had poorer scores than girls in body and hand motor skills and tracing (b=-0.45, -0.68 and -1.5, all p<0.019). Children with behavioural difficulties had significantly poorer outcomes in most developmental domains. Some of the associations with SES and sex were stronger in older than in younger children. Associations between gestational age and motor development were weaker in older children. We did not find significant associations between child development and sleep duration, breastfeeding duration or overweight/obesity. CONCLUSION: Some factors had a protective, others an adverse effect on development of children under 6 years of age. The effect of SES and sex increased, while the effect of gestational age decreased with age. TRIAL REGISTRATION NUMBER: NCT02550236.