During my medical training, we were taught that if a patient responds to a treatment, it doesn’t necessarily mean that every patient will respond in the same way. The results in a single patient might be due to chance so it was important to look at the results of well-designed research studies before we could conclude that the treatment really worked. In statistics, “N” refers to the sample size in an experiment so we referred to these individual observations as “N-of-1” experiments (and we did not look at them very favorably).
Unfortunately, there are lots of problems with research studies – they take a long time to complete, the patients in the studies are very carefully selected and may be very different from you, there is often bias in the way the results are interpreted, etc.
What if doctors and patients had tools that allowed them to design high-quality experiments specifically for the individual patient?
Researchers are beginning to create tools to help patients perform experiments on themselves. It may seem unnecessary to do a formal experiment when testing your response to a drug or treatment but the truth is that we are all biased – we need to have specific measurements to be sure a treatment is working. These tools may be things like continuous measurements of pulse or blood pressure or text messages reminding us to take a measurement or record an observation.
N-of-1 experiments are now being seen as a valuable approach to figuring out the best treatment for an individual patient. And they are a lot quicker and less expensive than the large research studies we have relied on for years. And if we can collect the results of these N-of-1 experiments using scientific methods, we can share data in a way that helps other people.
Thomas Goetz has founded a company called Iodine that is attempting to do just that – take the experiences of individual patients about their responses to drugs in order to help other people with the same medical condition figure out which drug is best for them. It will be important to have a database of lots of patients and their experiences for the information to help guide decisionmaking but it is a great start and the site is very well designed and user-friendly.
Earlier this year, President Obama announced a $215 million national Precision Medicine Initiative. Precision medicine takes individual variability into account when prescribing treatments. For example, one person may respond to a drug differently than another based on genetic, ethnic or environmental factors. Most of the focus of precision medicine is on the important work of looking at the genome – the complete DNA – of individual patients in order to target the therapy.
In a great article in Nature, Nicholas Schork outlines the importance of doing well-designed and well-documented N-of-1 research studies as part of precision medicine. He suggests that we begin by taking a more scientific approach to everyday clinical care by turning individual treatment decisions into N-of-1 experiments and then pooling all the information together to help others.
N-of-1 experiments, once something I tried to avoid, may prove to be an important part of precision medicine.