Not only do over 40 million adults in the U.S. get less than the recommended seven to nine hours of sleep per night, but the quality of sleep they are getting isn’t all that great. According to the National Sleep Foundation’s 2014 Sleep Health Index™, 35 percent of Americans report their sleep quality as either ‘poor’ or ‘only fair’.
The effects of this sleep deficit are significant. The National Institutes of Health reports50 to 70 million Americans have chronic sleep disorders and/or periodic troubles with sleeping, which can significantly diminish their health, alertness and safety.
Sleep quality is indisputably an issue affecting many Americans, but how do we quantify quality sleep?
Establishing Standard Guidelines
This year, the National Sleep Foundation partnered with the Consumer Technology Association's (CTA) Standards Sleep Subcommittee to define terms for describing sleep states and indicate the functionality required in consumer devices for measuring sleep behavior. On October 19th, 2016, the CTA announced the publication of a new standard, the Definitions and Characteristics for Wearable Sleep Monitors.
This collaboration to create a common language for the characterization of sleep addresses the lack of, and necessity for, accepted definitions that bridge the gap between consumer and medical understanding of sleep itself.
Incorporating the CTA’s Standards into Wearable Devices
To achieve the publication of CTA’s new standard, sleep scientists and representatives from technology companies joined to agree on meanings based on the best knowledge available on sleep science today. These CTA standards can help establish a common ground for measuring sleep, giving the terms tangible meaning across wearable devices. These devices, and their insights, will now have more actionable outputs for individuals and those in the field of study.
In his review “Recent Developments in Home Sleep-Monitoring Devices,” Dr. Matt Bianchi says, “Despite the clear utility of the laboratory polysomnogram (PSG) in clinical sleep medicine, issues of cost and inconvenience have motivated the development of portable devices capable of evaluating sleep in the home.”
Devices that can easily and comfortably, yet still credibly, collect data democratize our ability to understand and act on sleep issues. Sleep monitoring can now bypass the lab limitations of the “atypical sleeping environment and the single-night snapshot,” according to Bianchi. He expands on this point, stressing that longitudinal data “is likely to prove invaluable for the discovery of intrinsic patterns of sleep variability.”
The Need for Standard Measurements
However, despite their convenience and accessibility, how helpful can consumer sleep monitoring devices really be if each device is using a different definition for terms like “sound sleep?”
In his review Dr. Bianchi points to one of many potential discrepancies in definitions: “The American Academy of Sleep Medicine scoring criteria utilizes a time interval of 30 seconds to define an epoch of sleep, with a ‘majority rules’ approach to assigning a stage to an epoch that contains features of more than one stage. Thus, if a device utilizes a time interval that is either shorter or longer than the AASM criteria, the validation results may differ. For example, shorter epochs may capture nuances of sleep architecture, while longer epochs or smoothing algorithms may yield a different image of sleep physiology.”
The Future of In-Home Sleep Wearables
Moving beyond their effectiveness at the individual level, fitness and sleep wearables are migrating from residing in a strictly consumer environment to a highly specialized world of research and clinical trials.
As researchers and medical professionals studying sleep begin to see the value of home monitoring and the large data sets consumer wearables provide, the stakes are changing. When evaluating subjects in clinical trials and patients with sleep disorders, performance expectations must be higher. The incorporation of devices in research aiming to better understand human health and disease necessitates wearable technology with standardized metrics.
The CTA’s new standards reflect the evolution of healthcare and human physiological research. As wearable devices become more integral to our understanding of the human body, they will continually need to be held to common standards. In order to maximize the benefits they provide, device manufacturers and scientists need to be speaking the same language. We applaud the efforts of the CTA in taking this difficult task on and are proud to contribute through our membership and participation.