That is the new Journal of Economic Literature survey by Dennis Epple, Richard E. Romano, and Miguel Urquiola. It is a fine piece, the best I have seen (and in fact one of the better survey pieces I’ve read on any literature), and it stresses such important distinctions as small- vs. large-scale voucher programs, and why that matters for interpreting various voucher tests. Here is the abstract:
We review the theoretical, computational, and empirical research on school vouchers, with a focus on the latter. Our assessment is that the evidence to date is not sufficient to warrant recommending that vouchers be adopted on a widespread basis; however, multiple positive findings support continued exploration. Specifically, the empirical research on small-scale programs does not suggest that awarding students a voucher is a systematically reliable way to improve educational outcomes, and some detrimental effects have been found. Nevertheless, in some settings, or for some subgroups or outcomes, vouchers can have a substantial positive effect on those who use them. Studies of large-scale voucher programs find student sorting as a result of their implementation, although of varying magnitude. Evidence on both small-scale and large-scale programs suggests that competition induced by vouchers leads public schools to improve. Moreover, research is making progress on understanding how vouchers may be designed to limit adverse effects from sorting, while preserving positive effects related to competition. Finally, our sense is that work originating in a single case (e.g., a given country) or in a single research approach (e.g., experimental designs) will not provide a full understanding of voucher effects; fairly wide-ranging empirical and theoretical work will be necessary to make progress.
…Vouchers have been neither the rousing success imagined by proponents nor the abject failure predicted by opponents…The most robust finding is that voucher threats induce public schools to improve.