Poverty and Dentistry

May 31, 2016
Posted by Jay Livingston

A couple of years ago, Marco Rubio (remember him?), the Heritage foundation, and others were making the ludicrous claim that if poor people would just get married, the rate of child poverty would fall by 80% or more. After all, a very large proportion of children in poverty lived in single-parent homes. These conservatives were mistaking correlation for cause, and the causal arrow might easily point the other way. When most of the men in sight are poor and without prospects for improving their lot, a woman with children might well choose to remain unwed. So instead of non-marriage leading to children in poverty, it is the general poverty of a population that makes for lower rates of marriage. 

To illustrate the folly of taking correlation as cause, I used the example of dentistry. People who go to the dentist are much less likely to be poor, and the poor were twice as likely to be toothless. By the logic of marriage-ends-poverty, we could conclude that visiting the dentist once a year would lower a person’s probability of being poor by 50%. (That blog post is here. )

I was being facetious about cause and effect. But it turns out that while dentistry may not cause prosperity, poor people think it’s important. Richard Reeves at The Brookings Institute (here) looks at reports on Colorado, a state where expansion of healthcare under Obamacare and Medicaid included dental coverage for those with incomes under $30,000.

Did low-income people take advantage of their new medical and dental benefits? No and yes, respectively. The Colorado Health Access Survey found that from 2009 to 2015, the rate of low-income Coloradans visiting the doctor changed only slightly. But visits to the dentist were another matter.

(Click on an image for a larger view.)

As the percent of low-income people with dental coverage rose to about 63%, the percent who actually visited the dentist rose to nearly that same proportion.

Reeves offers no explanation for why the poor were so much more likely to use their dental coverage than their medical. Perhaps it’s because the pain of a toothache is hard to ignore. Also, with many medical symptoms, a visit to the doctor is only the beginning, and the symptom improves gradually, with medications, treatments, and other regimens, But the pain of a toothache can be ended with a single visit to the dentist.