title: Waste, Leaks, and Failures in the Biomarker Pipeline.
abstract: The large, expanding literature on biomarkers is characterized by almost ubiquitous significant results, with claims about the potential importance, but few of these discovered biomarkers are used in routine clinical care.
  
  
  
  The pipeline of biomarker development includes several specific stages: discovery, validation, clinical translation, evaluation, implementation (and, in the case of nonutility, deimplementation). Each of these stages can be plagued by problems that cause failures of the overall pipeline. Some problems are nonspecific challenges for all biomedical investigation, while others are specific to the peculiarities of biomarker research. Discovery suffers from poor methods and incomplete and selective reporting. External independent validation is limited. Selection for clinical translation is often shaped by nonrational choices. Evaluation is sparse and the clinical utility of many biomarkers remains unknown. The regulatory environment for biomarkers remains weak and guidelines can reach biased or divergent recommendations. Removing inefficient or even harmful biomarkers that have been entrenched in clinical care can meet with major resistance.
  
  
  
  The current biomarker pipeline is too prone to failures. Consideration of clinical needs should become a starting point for the development of biomarkers. Improvements can include the use of more stringent methodology, better reporting, larger collaborative studies, careful external independent validation, preregistration, rigorous systematic reviews and umbrella reviews, pivotal randomized trials, and implementation and deimplementation studies. Incentives should be aligned toward delivering useful biomarkers.
authors.affiliation: Departments of Medicine, Health Research and Policy, and Statistics, and the Meta-Research Innovation Center at Stanford (METRICS), Stanford University, Stanford, CA; jioannid@stanford.edu.
authors.forename: John P A
authors.initials: JPA
authors.lastname: Ioannidis
authors.affiliation: Department of Clinical Epidemiology, Biostatistics & Bioinformatics, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands.
authors.forename: Patrick M M
authors.initials: PMM
authors.lastname: Bossuyt
mesh_terms: D015415:Biomarkers; D035843:Biomedical Research / Q000592:standards* / Q000639:trends*; D000068456:Clinical Studies as Topic / Q000592:standards; D006801:Humans
chemical_list: D015415:Biomarkers