Structural and process features. Researchers compare the effects, if any, that programs employing varying conditions and practices have on the children attending them. Correlation and causation. To answer these questions, researchers try to isolate specific conditions or practices within a child care setting, and then confirm that those factors are actually correlated with certain positive or negative effects. To show effects requires difficult and expensive controlled experimental studies that raise many practical and ethical issues.
Few studies can state unequivocally that high quality causes positive effects.
Child care quality also had a consistent positive correlation with children's cognitive and language development. High quality is not the chief cause or predictor of positive outcomes, nor is low quality the chief cause or predictor of negative outcomes. Researchers documented a greater likelihood of responsible behaviors including fewer arrests and higher IQs, education levels, incomes, rates of home ownership, and rates of marriage among participants as compared with nonparticipants, even after 27 years. High-quality child care is in short supply. Love et al.