Does Education Improve Health? A Reexamination of the Evidence from Compulsory Schooling Laws
Improving the long-term health of the population is clearly an important goal for policymakers. It is also likely to become even more so in the coming years with the aging of the baby boomers and the anticipated health-related costs that will accompany this demographic change. Therefore, understanding which policy levers might improve health is of interest. In a provocatively titled front page article, “A surprising secret to a long life: Stay in school,” the New York Times recently suggested that many researchers now believe that education is the key factor in promoting health. While social scientists have long known that there is a strong positive correlation between education and longevity, many researchers have speculated that this association was not truly causal, meaning one didn’t necessarily lead to the other. Rather, the link was thought to reflect either the fact that for a variety of other reasons (for example, parental income and personal attitudes), people who tend to acquire more schooling also tend to be in better health, or that healthier children stayed in school longer. Of course, in the absence of evidence of a causal link, there is no reason to expect that policies aimed at increasing educational attainment will result in improvements in health.
The author recently discovered a programming error that affected some of the results in table 3 where a cohort time trend was incorrectly coded. Table 3 shows estimates of the effect of education on mortality using compulsory schooling laws as instruments. The initially published results had suggested that specifications that included state-specific cohort trends resulted in much smaller coefficients (in absolute value) that were statistically insignificant. The corrected results suggest that the point estimates are much closer to 0, are of the wrong sign and have larger standard errors than the previously published estimates. This further suggests that there is little compelling evidence suggesting a causal link between education and mortality based on Census data and compulsory schooling laws. A few other minor errors were also fixed in the table. A copy of the revised table is included at the end of the full article.