What is Big Think?  

We are Big Idea Hunters…

We live in a time of information abundance, which far too many of us see as information overload. With the sum total of human knowledge, past and present, at our fingertips, we’re faced with a crisis of attention: which ideas should we engage with, and why? Big Think is an evolving roadmap to the best thinking on the planet — the ideas that can help you think flexibly and act decisively in a multivariate world.

A word about Big Ideas and Themes — The architecture of Big Think

Big ideas are lenses for envisioning the future. Every article and video on bigthink.com and on our learning platforms is based on an emerging “big idea” that is significant, widely relevant, and actionable. We’re sifting the noise for the questions and insights that have the power to change all of our lives, for decades to come. For example, reverse-engineering is a big idea in that the concept is increasingly useful across multiple disciplines, from education to nanotechnology.

Themes are the seven broad umbrellas under which we organize the hundreds of big ideas that populate Big Think. They include New World Order, Earth and Beyond, 21st Century Living, Going Mental, Extreme Biology, Power and Influence, and Inventing the Future.

Big Think Features:

12,000+ Expert Videos


Browse videos featuring experts across a wide range of disciplines, from personal health to business leadership to neuroscience.

Watch videos

World Renowned Bloggers


Big Think’s contributors offer expert analysis of the big ideas behind the news.

Go to blogs

Big Think Edge


Big Think’s Edge learning platform for career mentorship and professional development provides engaging and actionable courses delivered by the people who are shaping our future.

Find out more

Does Medicaid Affect Health? Part II

May 14, 2013, 12:36 PM

(Caution – this piece is wonkish.)

An interesting aspect of the Oregon Health Study, which I wrote about a little while ago, is that it uses the “intent to treat” format of a randomized controlled trial. In this kind of study, the control group and treatment group are still randomized. The people in the treatment group, however, don’t necessarily receive the treatment; they just get the opportunity (or have the “intent”) to receive it. This has deep implications for the study’s results.

People who were randomized into the “intent to treat” group got the chance to enroll in Oregon’s Medicaid program. Not all of them signed up. If there were any uniform differences between the people who signed up and those who didn’t, it would have affected the study’s results. I think there probably were, and they did.

Who were the people most likely to sign up for Medicaid, given the chance? I’d guess they fell into two groups: 1) people who cared a lot about their health and seized the opportunity to get insurance, and 2) people who were really sick and knew they needed health care. In other words, the healthiest and sickest people may have been the ones who signed up.

A few months after the lottery, the researchers checked to see whether people with Medicaid coverage had better scores in cholesterol, blood pressure, and other health tests. They didn’t find much of a difference in several areas.

I don’t think this is surprising, if you believe my story about self-selection and adverse selection in the previous paragraph. The healthiest people were already doing everything to be healthy, and the sickest may have been too sick to improve in such a short period of time. The people who might have shown a change even over a few months may have been the least likely to sign up for Medicaid, even when they had the chance.

The “intent to treat” format does not alleviate selection problems within the “intent to treat” group. As the researchers’ appendix explains, it simply magnifies the effect measured for the selected subset of the group. Until they reveal more about the initial health differences between the two subsets of the “intent to treat” group, I’ll have a hard time believing their results.

Image courtesy of Shutterstock


Does Medicaid Affect Health...

Newsletter: Share: