Childcare provided for three-year-olds by relatives and childminders is marginally better than centre-based care for socio-emotional development at age five, according to a report by the Economic and Social Research Institute.
Centre-based care for over 30 hours a week scores particularly badly.
However, teachers report that children from disadvantaged backgrounds fare better in centre-based care.
ESRI researchers compared outcomes for children placed with relatives, childminders and in centres such as crèches.
They surveyed a representative sample of around 9,000 children who are participating in the 'Growing Up in Ireland' study.
The research assessed mothers' and teachers' feedback on children's socio-emotional outcomes regarding their pro-social skills, such as sharing or kindness to younger children.
It also assessed reports from the same sources of the children's socio-emotional difficulties, including conduct problems, emotional difficulties, hyperactivity and inattention as well as peer problems.
After taking account of a range of child, parent, family and neighbourhood-level characteristics the study found that children cared for by relatives - typically grandparents - at age three had somewhat fewer socio-emotional difficulties and better social skills at five than those receiving full-time care from their parents.
Children cared for by a non-relative such as a childminer at age three were rated by both parents and teachers as having fewer socio-emotional difficulties, in particular, fewer emotional and peer problems than children who had been in full-time parental care.
However, where children in centre-based care were concerned, teacher ratings showed slightly higher socio-emotional difficulties compared to children in parental care only, particularly for those receiving over 30 hours of centre-based care.
In contrast, parent-rated total socio-emotional difficulties scores did not differ between children who experienced centre-based care at age three and those in full-time parental care.
For a number of disadvantaged groups, teachers reported that centre-based care had a positive effect on the socio-emotional development of five-year-olds.
Researchers report that centre-based care is associated with a reduction in total difficulties for children in the lowest social class categories.
They also say there was an increase in the pro-social scores for children from lone parent households attending such centres.
They caution that the effects of childcare are small and that both the type and the hours of care at age three explained less than 1% of the variation in children's scores.
Other important factors associated with socio-emotional outcomes were the child's health, gender, socio-economic background, and family structure.
Other family characteristics - such as parenting style and parental stress - had a greater impact on socio-emotional development than childcare.
The report also states that greater difficulties were found among boys; children living in households experiencing financial difficulties and those living in less safe areas.
