On the reliability of wearable technology: A tutorial on measuring heart rate and heart rate variability in the wild

Abstract

Wearable sensors are quickly making their way into psychophysiological research, as they allow collecting longitudinal and ecologically valid data. The present tutorial considers fidelity of physiological measurement with wearable sensors, focusing on reliability. We elaborate why ensuring reliability for wearables is important and offer statistical tools for assessing wearable reliability for between participants and within-participant designs. The framework offered here is illustrated using several brands of commercially available heart rate sensors. Our hope is that by systematically quantifying measurement reliability, researchers will be able to make informed choices about specific wearable devices and measurement procedures that meet their research goals.