Author Affiliations: Department of Hygiene and Epidemiology, University of Ioannina School of Medicine, and Biomedical Research Institute, Foundation for Research and Technology–Hellas, Ioannina, Greece (Dr Ioannidis); Institute for Clinical Research and Health Policy Studies, Tufts Medical Center, Department of Medicine, Tufts University School of Medicine, and Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts (Dr Ioannidis); and Department of Epidemiology and Biostatistics, Imperial College of Medicine, London, England (Dr Tzoulaki).
Each year, researchers identify thousands of potential new “tools” for predicting patients' medical futures. There is heightened interest for discovering, validating, and incorporating into clinical practice predictors that improve treatment choices and outcomes thereof.1,2 Thousands of articles report on potential predictors. A search of PubMed clinical queries under prognosis (specific strategy) yields 165 746 articles for cancer, 72 354 for cardiovascular disease, and even 3749 for rheumatoid arthritis. These run the gamut, including genetic tests, biomarkers, and an increasing variety of imaging modes, lengthening the list of candidate predictors.3 However, very few of these proposed predictors eventually change practice. Why? What makes a good predictor?
Ioannidis JPA, Tzoulaki I. What Makes a Good Predictor?The Evidence Applied to Coronary Artery Calcium Score. JAMA. 2010;303(16):1646-1647. doi:10.1001/jama.2010.503