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Jena AB, Philipson TJ.Jena AB, et al. Among authors: philipson tj.J Health Econ. 2008 Sep;27(5):1224-36. doi: 10.1016/j.jhealeco.2008.05.010. Epub 2008 Jun 5.J Health Econ. 2008.PMID: 18619695