Evidence-based care has been defined as “the conscientious, explicit, and judicious use of current best evidence in making decisions about the care of individual patients.”1 However, until now, most treatments have been designed with a “one-size-fits-all” approach: useful for some patients but not helpful or even harmful for others.2 Analyses of clinical trials generally focus on summarizing overall average treatment effects without more deliberate investigation of which patients actually benefit. For example, if the number needed to treat using a new therapy is 50, then 50 individuals need to receive this treatment for 1 individual to benefit. But what characterizes that benefiting individual? Therapies can also both help and harm, successfully improving some outcomes while also placing patients at increased risk for other adverse events.
Pencina MJ, Peterson ED. Moving From Clinical Trials to Precision MedicineThe Role for Predictive Modeling. JAMA. 2016;315(16):1713-1714. doi:10.1001/jama.2016.4839