Key Publications

• Groeneveld, M.G., H.J. Vermeer, Van IJzendoorn, M.H. & Linting, M. (2008). Welbevinden en stress van kinderen in de kinderopvang. Een vergelijking van kinderdagverblijven en gastoudergezinnen. Rapport Universiteit Leiden. The rapport is available in pdf (see below).
• Van IJzendoorn, M.H., Tavecchio, L.W.C., & Riksen-Walraven, J.M.A. (2004). De Kwaliteit van de Nederlandse kinderopvang [The quality of Dutch childcare]. Amsterdam/Meppel: Boom
• Linting, M., Meulman, J.J., Groenen, P.J.F., & Van der Kooij, A.J. (in press). Nonlinear Principal Components Analysis: Introduction and Application. Psychological Methods. (In this paper the technique of Nonlinear Principal Components Analysis is applied to data from the NICHD Early Childhood Research Network).
• Love, J.M., Harrison, L., Sagi-Schwartz, A.. Van IJzendoorn, M.H., Ross, C., Ungerer, J.A. et al. (2003). Child care quality matters: How conclusions may vary with context. Child Development, 74, 1021-1033.
  Abstract
  Three studies examined associations between early child care and child outcomes among families different from those in the National Institute of Child Health and Human Development (NICHD) Early Child Care Research Network study. Results suggest that quality is an important moderator of the amount of time in care. Thus, the generalizability of the NICHD findings, conducted in three national contexts, with different regulatory climates, ranges of child care quality, and a diversity of family characteristics, suggest a need for more complete estimates of how both quality and quantity of child care may influence a range of young children's developmental outcomes.
• Schipper, J.C., Van IJzendoorn, M.H., & Tavecchio, L.W.C. (2004). Stability in center day care: Relations with children's well-being and problem behavior in day care. Social Development, 13, 531-550.
  Abstract
  Mothers and primary professional caregivers of 186 children, aged 6-30 months, participated in this study in which a new measure for daily stability in a center day care was developed, describing staffing, grouping, and program features. Relative contributions of infants' daily experiences of care stability, quality of care, and mother's daily stress to the child's adjusstment to day care were analyzed with hierarchical regressions. The child's adjustment was assessed with the Child Behavior Checklist (Achenbach, 1997) and with the Leiden Inventory for the Child's Well-being in Day Care. Children enrolled in fewer care arrangements showed less internalizing behavior and more well-being in the day care setting. Children had higher well-being scores when trusted caregivers were more available. Mother's family management stress was related to more internalizing problem behavior. Interactions between mother's daily stress and stability in care were foundd to affect the child's adjustment to day care.
• Vermeer, H.J., Van IJzendoorn, M.H., De Kruif, R.E.L., Fukkink, R.G., Tavecchio, L.W.C., Riksen-Walraven, J.M.A., & Van Zeijl, J. (2005). Kwaliteit van Nederlandse kinderdagverblijven: Trends in kwaliteit in de jaren 1995-2005 [Quality in Dutch childcare centers: Trends in quality between 1995-2005]. Amsterdam: NCKO.
• Vermeer, H.J., & Van IJzendoorn, M.H. (2006). Children's elevated cortisol levels at daycare: A review and meta-analysis. Early Childhood Research Quarterly, 21, 390-401.
  Abstract
  We reviewed nine studies in which children's cortisol levels at center daycare were assessed. Our first hypothesis, concerning intraindividual differences in cortisol levels across home and daycare settings, was also tested in a meta-analysis. Our main finding was that at daycare children display higher cortisol levels compared tot the home setting. Diurnal patterns revealed significant increases from morning to afternoon, but at daycare only. The combined effect size for seven pertinent studies (n=303) was r=.18 (Cl. .06-.29, p=.003). We examined all papers on possible associations between cortisol levels and quality of care, and the influences of age, gender, and children's temperament. Age appeared to be the most significant moderator of this relation. It was shown that the effect of daycare attendance on cortisol excretion was especially notable in children younger than 36 months. We speculate that children in center daycare show elevated cortisol levels because of their stressful interactions in a group setting.