The quality and comparability of child care data in U.S. surveys.

This paper examines the quality and comparability of child care data obtained from eight waves of data from four nationally representative data sources: the National Longitudinal Survey of Youth (1986 and 1988), the Survey of Income and Program Participation (1986, 1987, 1988, and 1990), the National Child Care Survey, and the National Survey of Families and Households. We examine whether different study designs and survey techniques for asking questions about child care produce similar results on both the levels and determinants of child care. We identified four main sources of difference in the data sets that could impact the quality and comparability of child care research: when the interview is conducted; screening questions used to determine who is asked about child care; the population of parents and children represented in the survey; and the way child care questions are asked. Our findings indicate that summer interviews and screening on mother's work status produce the largest differences in the levels and effects of child care across these studies. Even after removing the effects of summer interviews and screening questions, however, substantial differences exist across the studies.