sentences:  McCartney’s research has focused on early experience and development, particularly with respect to child care, early childhood education, and poverty.She has published more than 150 articles and book chapters on those topics and was the principal researcher for Child Care and Child Development, a 20-year study published in 2005 that examined whether early and extensive child care disrupted the mother-child relationship.She co-edited "Experience and Development", "The Blackwell Handbook of Early Childhood Development", and "Best Practices in Developmental Research Methods".