What is the basis for the argument that poor Americans will be healthier if they are required to pay substantially more for health care? It appears that proponents like Ms. Verma have looked at research and concluded that having Medicaid is often no better than being uninsured - and thus that any private insurance, even with enormous deductibles, must be better. But our examination of research in this field suggests this kind of thinking is based on a classic misunderstanding: confusing correlation for causation.
What do you take from this hypothetical headline: "Reading the Research Digest blog is associated with higher intelligence"? How about this one: "Reading this blog might increase your intelligence"? According to science writing guides like HealthNewsReview.org, taking the first correlational finding from a peer-reviewed article and reporting it for the public using the second wording, implying causation, is a sin of exaggeration, making a relationship appear more causal than the evidence suggests.
Another example of news coverage over-stating the causal relationship between two things that research has demonstrated have some *association*. Good discussion of the particular headlines.