Thursday, March 12, 2009

_____ Effectiveness

I tried to post this yesterday before a meeting. I got bumped from the web and was not able to post. Now, I'll post this and later today another entry thinking about different types of analyses.

I am about to attend an afternoon meeting on comparative effectiveness. For those who are not familiar with he medical terminology, here is a brief primer. I will try to explain the difference between clinical effectiveness, comparative effectiveness, and cost-effectiveness. The United States has historically largely relied on clinical effectiveness research for guiding policies about whether products like pharmaceuticals or medical devices should be approved and covered. I will argue that we need to be concerned more about cost-effectiveness. Comparative effectiveness is a nice in-between step.

Clinical effectiveness could be defined as the result of research in which a new drug, device, or intervention is compared with doing nothing. This is usually referred to as a placebo in drug research. The key here is that the product can then be called effective if it changes a clinical outcome. It becomes one of many things that are available for providers and patients to choose to use when a patient has a medical condition that needs to be cured or at least to have the symptoms controlled.

Comparative effectiveness has numerous definitions. The one that seems to be used by the National Institutes of Health in the United States at the moment focuses on figuring our which treatment (among many that many have undergone clinical effectiveness research) is most effective. This involves comparing treatments with one another rather than comparing treatments with nothing or a placebo.

Cost-effectiveness (and in a later entry I can provide details on the many interpretations of cost-effectiveness) allows us to address questions of which treatment provides the best value. This may be the most effective from a comparative effectiveness analysis. It may also be one that is among the effective but not most effective if the most effective product is also highly expensive. Some products may be so expensive that their added effectiveness is not worth the spending.

So we have relied on simply making sure that a product is effective to make drugs available. We need to move toward a system where the value is systematically assessed to ask whether we should be spending money on particular options. This is one way in which we might control costs. There are others. The key is that we need to control costs and head to head comparisons among alternatives to determine which is most effective is just the start.


  1. Hi, I love reading your short but insightful postings. Can you comment on why and in what condition cost-effectiveness analysis can be cost-effective?

  2. Cost-effectiveness analysis can be cost-effective when it will actually make a differnece in the decision making. There is, interestingly enough, a whole science of figuring out when cost-effectiveness is cost-effective.