The Future of Children, Princeton - Brookings: Providing research and analysis to promote effective policies and programs for children.

Most of the major evaluations summarized in the articles in this journal issue are of reasonably good quality: all include comparison groups, most of them developed through randomized assignment; many include measures of both implementation and outcome; and many assess a variety of outcomes. However, they have weaknesses, too. The individualization of service content and delivery inherent in home visiting programs may make it hard to see differences across a whole group, because, in fact, the group is not getting the same treatment. A mix of standardized tests and less-well-recognized measures, not all of which had been previously tested with similar populations, were used. The relatively high attrition rates from some programs, and the lower, but sometimes still high attrition rates from their studies may weaken some of the conclusions that can be drawn from the evaluations. Results vary across program sites, suggesting that generalization of results may be limited.

Nevertheless, these evaluations stand as some of the best in the home visiting field. Interpretation of evaluation results is an art, not a science, but these studies are sturdy enough to provide guidance to policymakers and practitioners.