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Feature Research in practice

Research versus the patient

BMJ 2013; 346 doi: (Published 21 January 2013) Cite this as: BMJ 2013;346:f332
  1. Bob Roehr, Freelance journalist
  1. 1Washington, DC
  1. BobRoehr{at}

Bob Roehr looks at the challenges of applying research averages to individual patients

“If it were not for the great variability among individuals, medicine might be a science and not an art.” Sir William Osler, 1892

Tension between the science and art of healthcare has never been greater. On the one hand is the certainty of P values generated by well designed double blinded randomized controlled trials. Means and medians from these studies are used as the foundation for treatment guidelines and insurance coverage.

But physicians know from experience that patients seldom comport with the statistics of pristine trials. Patients are messy, they come with comorbidities, differing biologies, their own desires and preferences that seldom match up exactly with what is seen on the clean pages of the scientific literature.

“There is probably no issue more exciting than this scientific notion that treatments—be they pharmaceutical treatments or system level interventions—may have differential effects depending on who the patient is,” says Joe V Selby. He is executive director of the Patient-Centered Outcomes Research Institute (PCORI), the independent organization established under the Affordable Care Act (ACA).

It might be frustrating that answers for individual patients are so slow in coming, but Selby points to advances that have been made over the past decades using averages. He adds, “Treatment heterogeneity is something real that we can study and act on.”

“As you increase the number of subgroups that you are able to include in your analysis, you zero in on the individual,” according to Selby.

“There has to be an important role for observational studies in an exploratory analysis looking for treatment heterogeneity,” he says. “If there is a lot of it, and it is common across a number of diseases, we are generally not going to find it in the kind of …

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