Do Higher Grades Mean Better Health?

The relationship between education and health has been discussed several times on this blog, most recently by Kevin. Kevin mentioned that there is a positive socioeconomic gradient: more educated people have better health on average. However, this does not imply that one causes the other. Kevin also mentioned recent research by Nils Braakmann, which examines the relationship between education and health, exploiting exogenous variation from a compulsory schooling law in the UK. Braakmann's results indicate "neither an effect of education on various health related measures nor an effect on health related behaviour, e.g., smoking, drinking or eating various types of food."

An interesting way of moving this research topic forward could be to focus more on quality of education rather than quantity of education. While there are many ways to consider how best to measure quality, one outcome that differentiates between students is grade point average, or grades. This metric has been the source of much debate (some of which I mentioned yesterday), but there is already some research which has set about examining the relationship between grades and health. (As an aside, readers may be interested to know that there is a positive relationship between college grades and subsequent earnings, as reported by McIntosh (2006), Loury and Garman (1995), Jones and Jackson (1990), Filer (1983) and Wise (1975).)

The research examining the relationship between grades and health came to my attention via an article by Roni Caryn Rabin in the Health section of the New York Times. The article refers to research done by Dr. Pamela Herd, and her colleagues at the University of Wisconsin in Madison. The research uses the Wisconsin Longitudinal Study, which has been following more than 10,000 people who graduated from Wisconsin high schools in 1957. "Those students who finished in the top 25 percent of their high school class were healthier, decades later, than the ones who finished in the bottom quarter... Even among those who each had 12 years of education, the person who performed better had better health".

Dr. Herd considered the possibility that better non-cognitive ability (or certain personality traits) could be driving both academic performance and health behaviour. NYT journalist Rabin provides more detail on Dr. Herd's thoughts on the matter:

"One explanation is that the same psychological characteristics that make for a hardworking student — like conscientiousness, dependability, good study habits and following the rules — also shape healthy behaviors. But when Dr. Herd examined personality surveys the graduates of 1957 filled out, controlling for variables like family background and childhood health, she didn’t find a strong correlation with health status... She’s convinced there’s something about the actual mastering of academic material that’s vital... the process of developing critical thinking skills and improving cognitive function."