Table 1.
Digital biomarker examples
| Categorya | Definitiona | Examplea | Corresponding Digital Biomarker Examples |
|---|---|---|---|
| Susceptibility/Risk Biomarker | A biomarker that indicates the potential for developing a disease or medical condition in an individual who does not currently have clinically apparent disease or the medical condition. | Breast Cancer genes 1 and 2 (BRCA1/2) mutations may be used as a susceptibility/risk biomarker to identify individuals with a predisposition to develop breast cancer. | [*] Detect cognitive changes in healthy subjects at risk of developing Alzheimer's disease using a video game platform.18 |
| [**] Classify adults at high risk of late-onset Alzheimer's disease using computerized cognitive testing.19 | |||
| [*] Reduce key risk metrics for anterior cruciate ligament injury during jump landings using inertial sensor-based feedback.20 | |||
| Diagnostic Biomarker | A biomarker used to detect or confirm the presence of a disease or condition of interest or to identify individuals with a subtype of the disease. | Repeated blood pressure readings obtained outside the clinical setting in adults 18 years and older may be used as a diagnostic biomarker to identify those with essential hypertension. | [*] Diagnose ADHD in children using eye vergence metrics.21 |
| [*] Detect arrhythmias using convolutional neural networks and a wearable single-lead heart monitor.22 | |||
| [*] Detect depression and Parkinson’s disease using vocal biomarkers.23 | |||
| [*] Diagnose asthma and respiratory infections using smartphone-recorded cough sounds.24 | |||
| Monitoring Biomarker | A biomarker measured serially for assessing the status of a disease or medical condition or for evidence of exposure to (or effect of) a medical product or an environmental agent. | Prostate-specific antigen (PSA) may be used as a monitoring biomarker when assessing disease status or burden in patients with prostate cancer. | [**] Monitor signs of Parkinson's disease using smartphone-based measurements.25 |
| [*] Quantify Parkinson’s disease severity using smartphones and machine learning.3 | |||
| [**] Track time and location of short-acting beta-agonist inhaler use using an attached wireless sensor.26 | |||
| [*] Predicting sleep/wake patterns from a 3-axis home-based accelerometer using deep learning.27 | |||
| [*] Detection of nocturnal scratching movements in patients with atopic dermatitis using accelerometers and recurrent neural networks.28 | |||
| Prognostic Biomarker | A biomarker used to identify the likelihood of a clinical event, disease recurrence, or progression in patients who have the disease or medical condition of interest. | Increasing prostate-specific antigen (PSA) may be used as a prognostic biomarker when evaluating patients with prostate cancer during follow-up, to assess the likelihood of cancer progression. | Stratify mental health conditions and predict remission using passively collected smartphone data.29 |
| Detect post-acute care deterioration in patients at home, applying machine learning to multi-sensor digital ambulatory monitoring.30 | |||
| Predictive Biomarker | A biomarker used to identify individuals who are more likely than similar individuals without the biomarker to experience a favorable or unfavorable effect from exposure to a medical product or an environmental agent. | Human leukocyte antigen allele (HLA)–B*5701 genotype may be used as a predictive biomarker to evaluate human immunodeficiency virus (HIV) patients before abacavir treatment, to identify patients at risk for severe skin reactions. | Predict autism risk in the siblings of children with autism, using an EEG biomarker.31 |
| Detect asymptomatic atrial fibrillation (AF) as a stroke risk factor, remotely through a connected device.32 | |||
| Pharmaco-dynamic/Response Biomarker | A biomarker used to show that a biological response has occurred in an individual who has been exposed to a medical product or an environmental agent. | Blood pressure may be used as a pharmacodynamic/response biomarker when evaluating patients with hypertension, to assess response to an antihypertensive agent or sodium restriction. | Measure cognitive performance with the Cambridge Neuropsychological Test Automated Battery (CANTAB) to test the effects of erythropoietin.33 |
| Measure blood pressure using a digital sphygmomanometer to assess response to antihypertensive therapy.34 |
aSelected from the FDA-NIH “Biomarkers, EndpointS, and other Tools” (BEST) classification for traditional biomarkers
[*] Digital biomarker under development
[**] Digital biomarker in use (in a clinical trial or an FDA cleared/approved digital health product, or a digital health app in use not requiring approval)