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. 2020 Mar 19;98(2):297–371. doi: 10.1111/1468-0009.12451

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© 2020 The Authors. The Milbank Quarterly published by Wiley Periodicals LLC on behalf of The Millbank Memorial Fund

This is an open access article under the terms of the http://creativecommons.org/licenses/by-nc/4.0/ License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.

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^aThese searches included manual searches of the MDRC, Abt Associates, Mathematica, and RTI websites and the Digest of Social Experiments published by the Urban Institute in 2004.

^bStudies were excluded at this stage of the review for the following reasons: study was not a relevant intervention; no relevant health effects were quantified; study was not based in the United States; no abstract was electronically available (eg, conference proceedings or commentaries).