ArticleBMJ open2021
Importance of accounting for sibling age when examining the association between family size and early childhood cognition, language and emotional behaviour: a birth cohort study.
Article in BMJ open, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 7 papers, 1 of them a synthesis that pooled it.
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Who cites it
7 citing papers in PubMed, 1 synthesis or guideline pooled it.
- Prevalence and Patterns of Prenatal Alcohol Exposure in Australian Cohort and Cross-Sectional Studies: A Systematic Review of Data Collection Approaches.International journal of environmental research and public health · 2022Pooled it
- Responsive Mealtime Matters: Feeding Autonomy and Varied Settings Were Associated With Problem-Solving Skills of Ethiopian Children Aged 6-23 Months.Maternal & child nutrition · 2026Article
- Family ecological influences on early childhood development in Shanghai, China: a cross-sectional study.BMC pediatrics · 2026Article
- Number of living siblings, social engagement, and cognitive decline among older Mexican adults.Social science & medicine (1982) · 2026Observational
- Family Size Across the Life Course and Cognitive Decline in Older Mexican Adults.The journals of gerontology. Series B, Psychological sciences and social sciences · 2025Article
- Linking the 1940 U.S. Census to the National Social Life, Health, and Aging Project: Novel Opportunity to Understand the Effects of Early-Life Residential Environment on Cognitive Aging.The journals of gerontology. Series B, Psychological sciences and social sciences · 2025Article
- Maternal Racial Differences and Socioeconomic Status in Preterm Infant Neurodevelopment, Feeding, and Growth.Nursing researchArticle
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Authors and funding
11 authors.
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Abstract
objectivesLarger sibships are associated with poorer cognitive and language outcomes but have different impacts on child emotional development. Previous studies have not taken into account sibling age, nor have impacts across multiple neurodevelopmental domains been considered in the same participant group. This study investigated the influence of family size indicators on early childhood cognitive, language and emotional-behavioural development. The effect of sibling age was considered by evaluating these relationships separately for different sibling age categories.
designProspective birth cohort study.
settingParticipants in the Barwon Infant Study were recruited from two major hospitals in the Barwon region of Victoria, Australia, between 2010 and 2013 (n=1074 children).
participantsThe 755 children with any neurodevelopmental data at age 2-3 years excluding twins and those with an acquired neurodisability. OUTCOME MEASURES: Cognitive and language development was assessed using the Bayley Scales of Infant and Toddler Development, Third Edition, and emotional-behavioural development was measured with the Child Behaviour Checklist for Ages 1½-5.
resultsGreater household size was associated with a reduced cognitive development score (adjusted mean difference (AMD) -0.66 per extra household member; 95% CI -0.96 to -0.37; p<0.001) without age-specific differences. However, poorer expressive language was only observed for exposure to siblings between 2-6 and 6-10 years older. Having siblings 2-6 years older was associated with less internalising behaviour (AMD -2.1 per sibling; 95% CI -3.1 to -1.0; p<0.001). These associations persisted after multiple comparison adjustment.
conclusionsThe influence of siblings on early childhood development varies substantially by sibling age and the neurodevelopmental outcome under study. Although family size alone appears important for cognitive development, age-specific findings emphasise the importance of sibling interaction in early childhood expressive language development and emotional behaviour.
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