JMIR Publications

ABSTRACT

Background:

Wearable activity trackers, including fitness bands and smartwatches, offer potential for disease detection by monitoring physiological parameters. However, their accuracy as specific disease diagnostic tools remains uncertain.

Objective:

Wearable activity trackers, including fitness bands and smartwatches, offer potential for disease detection by monitoring physiological parameters. However, their accuracy as specific disease diagnostic tools remains uncertain.

Methods:

Ten electronic databases were searched for studies published from inception to 1 April 2023. Studies were eligible if they used a wearable activity tracker to diagnose or detect a medical condition or event (e.g., falls) in free-living conditions in adults. Meta-analyses were performed to assess overall area-under-curve (AUC, %), accuracy (%), sensitivity (%), specificity (%) and positive predictive value (PPV, %). Subgroup analyses were performed to assess device type (Fitbit, Oura ring and mixed). Risk of bias was assessed using the Joanna Briggs Institute Critical Appraisal Checklist for Diagnostic Test Accuracy Studies.

Results:

28 studies were included, involving a total of 1,226,801 participants (mean age range: 28.6 to 78.3). 16 studies (57.1%) used wearables for diagnosis of COVID-19, 5 (17.9%) for atrial fibrillation, 3 (10.7%) for arrhythmia or abnormal pulse, 3 (10.7%) for falls and 1 (3.6%) for viral symptoms. The devices used were Fitbit (n=6), Apple watch (n=6), Oura ring (n=3), a combination of devices (n=7), Emphatica E4 (n=1), Dynaport MoveMonitor (n=2), Samsung Galaxy Watch (n=1) and other/not specified (n=2). COVID-19 detection: Meta-analyses showed a pooled AUC of 80.2% (95% CI: 71.0-89.3%), an accuracy of 87.5% (95% CI: 81.6-93.5%), a sensitivity of 79.5% (95% CI: 67.7-91.3%), and specificity of 76.8% (95% CI: 69.4-84.1%). Atrial fibrillation detection: Pooled PPV was 87.4% (95% CI: 75.7-99.1%), sensitivity was 94.2% (95% CI: 88.7-99.7%) and specificity was 95.3% (95% CI: 91.8-98.8%). Falls detection: Pooled sensitivity was 81.9% (95% CI: 75.1-88.1%) and specificity was 62.5% (95% CI: 14.4-100%).

Conclusions:

Wearable activity trackers show promise in disease detection, with notable accuracy in identifying atrial fibrillation and COVID-19. While these findings are encouraging, further research and improvement are required to enhance their diagnostic precision and applicability. Clinical Trial: PROSPERO ID: CRD42023407867.