Glossary · Study designUpdated September 28, 2026

What is a biomarker?

A biomarker is a characteristic that is measured as an indicator of normal biological processes, disease processes or responses to an exposure or intervention. It can be molecular, imaging-based, physiological or digital.

  • Biomarker in plain language
  • How it works in practice
  • Related terms

Free sandbox · No credit card · 21 CFR Part 11 aligned

Study design

Biomarker

noun · clinical research

A defined characteristic measured as an indicator of normal biological processes, pathogenic processes, or responses to an exposure or intervention.

Related terms

Surrogate endpointPredictive biomarkerDigital biomarkerReference intervalEndpoint

In short

  • The FDA-NIH BEST resource groups biomarkers into seven categories: susceptibility/risk, diagnostic, monitoring, prognostic, predictive, pharmacodynamic/response and safety.
  • Trials use biomarkers to select participants (for example amyloid confirmation in Alzheimer's trials), stratify randomisation, show pharmacological activity and monitor safety.
  • A biomarker validated to predict clinical benefit can serve as a surrogate endpoint, such as HbA1c or LDL cholesterol.
  • Digital biomarkers come from wearables and sensors, such as step count, heart rate variability or speech features.

Categories

Biomarker categories with examples

CategoryAnswersExample
Susceptibility / riskWho is likely to develop the disease?Genetic risk variants
DiagnosticDoes the person have the disease?Blood glucose for diabetes
MonitoringHow is the disease changing?HbA1c over time
PrognosticWhat is the likely course?Tumour stage markers
PredictiveWho will respond to this treatment?Target mutation for a targeted therapy
Pharmacodynamic / responseIs the drug acting on its target?Change in a pathway marker after dosing
SafetyIs there toxicity?Liver enzymes, creatinine

In Capture

Biomarker and lab data captured with its reference ranges

Lab and biomarker results sit in lab forms with analytes as rows, units and reference ranges by sex and age. Out-of-range values are flagged at entry, alert values are routed to the medical monitor, and the AI form builder drafts analyte tables from a lab manual or range sheet.

  • Reference ranges per laboratory, by sex and age.
  • Alert values routed with acknowledgement.
  • AI-drafted lab tables for review.
Lab data and reference range management
Site 02 · City Hospital Lab

Haemoglobin HGB · g/dL

3 strata
  • General13.0 to 17.0
  • Female 18-6412.0 to 15.5
  • Female 65+11.5 to 15.0
+ Add stratumNo Male 65+ stratum: general range applies

FAQ

Common questions

Something not covered here? Ask us directly.

What is a biomarker in simple terms?

Something you can measure, such as a blood test, image or sensor reading, that tells you about a biological process, a disease or a response to treatment.

What is the difference between a biomarker and a surrogate endpoint?

A surrogate endpoint is a biomarker that has been shown, or is reasonably likely, to predict clinical benefit and is used in place of a clinical outcome.

What is a predictive biomarker?

One that identifies people more likely to respond, or to respond differently, to a specific treatment.

What is a digital biomarker?

A biomarker collected by digital devices such as wearables or smartphones.

Lab and biomarker data, ranged at entry

Draft analyte tables with AI. Free sandbox.

Try Capture free