The Impact of Iodine Deficiency Eradication on Schooling: Evidence from the Introduction of Iodized Salt in Switzerland
This paper examines the impact of salt iodization in Switzerland in the 1920s and 1930s on schooling outcomes. Iodine deficiency in utero causes mental retardation, and correcting the deficiency is expected to increase the productivity of a population by increasing its cognitive ability. The exogenous increase in cognitive ability brought about by the iodization program is also useful in the context of disentangling the effects of innate ability and education in later-life outcomes. I identify the impact of iodization in three ways: first, in a differences-in-differences framework, I exploit geographic variation in iodine deficiency, as well as the fact that the nationwide campaign to decrease iodine deficiency began in 1922. Second, I use spatial and temporal variation in the introduction of iodized salt across Swiss cantons, and examine whether the level of iodized salt sales at the time of oneâ€™s birth affected oneâ€™s educational attainment. Third, I employ a fuzzy regression discontinuity design and use jumps in sales of iodized salt across Swiss cantons to identify the effect of iodization, by comparing outcomes for those born right before and right after these sudden changes in the treatment environment. These approaches indicate that the eradication of iodine deficiency in previously deficient areas increased the schooling of the population significantly. The effects are larger for females than for males, which is consistent with medical evidence showing that women are more likely to be affected by iodine deficiency disorders than men.
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- Imbens, Guido W. & Lemieux, Thomas, 2008.
"Regression discontinuity designs: A guide to practice,"
Journal of Econometrics,
Elsevier, vol. 142(2), pages 615-635, February.
- Guido Imbens & Thomas Lemieux, 2007. "Regression Discontinuity Designs: A Guide to Practice," NBER Technical Working Papers 0337, National Bureau of Economic Research, Inc.
- Guido Imbens & Thomas Lemieux, 2007. "Regression Discontinuity Designs: A Guide to Practice," NBER Working Papers 13039, National Bureau of Economic Research, Inc.
- Feyrer, James & Politi, Dimitra & Weil, David N., 2010. "The Economic Effects of Micronutrient Deficiency: Evidence from Salt Iodization in the United States," SIRE Discussion Papers 2010-10, Scottish Institute for Research in Economics (SIRE).
- Dimitra Politi & David N. Weil & James Feyrer, 2011. "The Economic Effects of Micronutrient Deficiency: Evidence from Salt Iodization in the United States," ESE Discussion Papers 201, Edinburgh School of Economics, University of Edinburgh.
- Edward Miguel & Michael Kremer, 2001. "Worms: Education and Health Externalities in Kenya," NBER Working Papers 8481, National Bureau of Economic Research, Inc.
- Michael Kremer & Edward Miguel, 2004. "Worms: Education and health externalities in kenya," Natural Field Experiments 00288, The Field Experiments Website.
- Erica Field & Omar Robles & Maximo Torero, 2009. "Iodine Deficiency and Schooling Attainment in Tanzania," American Economic Journal: Applied Economics, American Economic Association, vol. 1(4), pages 140-169, October.
- Hoyt Bleakley, 2007. "Disease and Development: Evidence from Hookworm Eradication in the American South," The Quarterly Journal of Economics, Oxford University Press, vol. 122(1), pages 73-117. Full references (including those not matched with items on IDEAS)