Final Ultrawonky Stat Geek Analysis of the Oregon Medicaid Study

Ticker

Monika Bauerlein,
CEO

Dear Reader,

The next few months are make-or-break for Mother Jones’ fundraising, and we need more online readers to pitch in than have been of late. In "It's Not a Crisis. This Is the New Normal," we take a level-headed look at the brutal economics of journalism, why investigative reporting like you get from us matters, and why we're optimistic we can grow our base of support in a big way—starting with hitting a huge $300,000 goal in just three weeks. Please learn more and donate if you can right now.

The next few months are make-or-break for Mother Jones’ fundraising. We need to raise $300,000 quickly, and we need more online readers to pitch in than have been. Please learn more in "It's Not a Crisis. This Is the New Normal," where we go into the brutal economics of journalism, and what makes Mother Jones unique and worth supporting if you can right now.

Fight disinformation: Sign up for the free Mother Jones Daily newsletter and follow the news that matters.

If you really want to understand the shortcomings of the Oregon Medicaid study, you should be reading Austin Frakt and Aaron Carroll over at The Incidental Economist. Frakt has one final post today in which he goes ultrawonky and calculates just how underpowered the study was if it wanted to get statistically significant results on the diabetes markers. It’s way over my head, so I’ll just pass along the headline result: the study was underpowered by at least a factor of 23. That is, the researchers would have needed a sample size 23 times larger than they had in order to find the results they were looking for.

The full writeup is here. Bottom line: this study was just too small. The fact that it didn’t find statistically significant results doesn’t really tell us anything at all, either good or bad, about the effect of Medicaid on health outcomes.