Choosing the Right Consumer Wearable for Your Research [2022 Edition]
With their ease of use, reduced cost, and the ability for continuous monitoring over long time periods, consumer wearables have wide applications in health research.
So, which consumer wearable is the best for health researchers? There are a lot of devices out there that have a ton of features to offer and it can be overwhelming. Are all of the latest features really necessary for your research or mostly just beneficial to fitness buffs? As this is a rapidly evolving area, there are factors in selecting a wearable device that researchers might overlook. We’re here to help.
What factors should you consider when selecting a wearable device for your research?
Although specific criteria will depend on your study, we recommend selecting your device by considering the following aspects:
- Metrics + Study Design
- Battery life
- Data Access
Is the device suitable for the participants being studied?
The priority of most study protocols is to minimize participant burden while simultaneously avoiding data loss. Since wearable technology is allowing researchers to recruit a more diverse group of participants, an important consideration is whether a device will be well-suited for your participant group. If the suitability of the device is incongruent with your participants' backgrounds and limitations, their adherence will likely be impacted. Suitability may be determined by how easy the device is to use, where it needs to be worn, its size and design, etc.
Ease of Use
Ease of use involves how the participant interacts with the device, including whether they need to remove the device regularly (if it is not waterproof for example), or maintain the device in any way. We recommend checking to see if your chosen device or vendor has a Help Center with documentation to make device operation easier on participants (and, in turn, researchers).
If your participants have functional limitations such as limited mobility, going with a chest strap instead of a ring or a smartwatch may be a challenge. If you’re interested in using a smartwatch and your participants have vision impairment issues, selecting a watch with a larger watch face may be a necessity.
Although on the pricier side, the Apple Watch Series 8 is a solid option if you are studying older participants as it offers features such as a large display, fall detection, and VoiceOver which reads what’s on the screen for you, making it one of the most friendly for the elderly. However, be aware that Apple Watches are currently only compatible with iPhones.
Certain participant groups may find the straps or belts provided by some devices too short or long to wear comfortably. While Oura rings can provide added comfort as they are usually custom-fit, this also means that it could be more challenging to reuse the rings with additional participants, leading to increased costs.
A project with adolescent participants may prioritize aesthetics since young people may be unwilling to wear a device if they feel it is unfashionable or draws unwanted attention. As an example, the ACTIVATE study for teens with type 1 diabetes is using the Garmin Vivosmart 4--a small and discreet smartwatch--with their teenage participants.
2. Metrics and Study Design
Is there evidence that the device provides the required level of measurement accuracy and precision in the metric of interest?
Another fundamental aspect of choosing a device is ensuring it collects the necessary data and has the required functions for your proposed study.
It comes as no surprise that device selection will be heavily influenced by the study protocol. With so many wearables to choose from, knowing your research goals can help you prioritize various criteria so you can select the best device for your specific experiment.
For instance, the choice of a wearable device to measure heart rate may be affected by the required measurement period. Some devices, such as a chest strap, may be inconvenient if worn for longer periods or may have insufficient battery or storage capacity.
Will multiple participants be reusing the same device in your study? If this is the case, the ease of resetting processes should be considered. Most vendors should have documentation on this.
While many researchers tend to stick with the brands they know, be aware that different brands of consumer wearables collect different types of data and not all devices within the same brand collect the same metrics. Even when they do, that doesn’t mean they collect the data at the same level of accuracy or quality. Devices within a brand may have different types or generations of sensors in the watches, as this meta-analysis on Fitbit devices discovered.
That being said, we suggest looking at validation studies comparing multiple devices for the metric(s) that you want to collect. Some devices may be extremely accurate for certain metrics but have a wider margin of error for others. If your study places a high priority on heart rate accuracy, the Polar H10 is a handy chest-strap device that is widely considered the most accurate method for obtaining heart rate since it uses electrocardiographic (EKG) rather than PPG-based signals. In terms of smartwatches, Apple’s Series 8 model comes with an FDA-approved electrocardiogram (ECG) sensor to measure heart rate.
3. Battery Life
If participants are required to wear or use a device for a specific number of days, then the device should have sufficient battery length to support this duration. The majority of smartwatches on the market have a battery life of about 3-7 days. There are devices, however, that can run anywhere from a few weeks without charging, to 6 months. This can be extremely beneficial if your participants may not have stable access to electricity, for example, or if you do not want to task them with charging their devices too often.
For a balance of features and battery life, we recommend the Garmin Vivosmart 5 and Fitbit Charge 5 which both last up to 7 days on a single charge (also depending on which metrics you’re collecting and the sampling rate).
We can’t talk about device choice without talking about the cost. Every study will have a budget (unfortunately) and wearable devices can range dramatically in price.
Although a researcher might be wary that the price of a consumer wearable will directly affect quality, this is luckily not the case. For example, the Garmin Vivosmart 4 runs at 130 USD at the time of this article (September 2022) and is able to collect sophisticated metrics such as interbeat interval data with a PPG sensor, allowing researchers to capture each individual heartbeat.
As the most prolific consumer wearables in the United States, some researchers choose to use Fitbit devices in their research and recruit participants who already own a device to save on cost. Some researchers similarly recruit through Apple’s ResearchKit those with Apple Watches. It is crucial to note again here that different generations of sensors and changes to algorithms may affect the data. Additionally, Apple Watches are currently only compatible with iPhones.
5. Accessing the Data
How are you going to access the data from the devices?
The researchers’ experience collecting and analyzing data from the devices should not be overlooked. The data acquisition process is an especially influential consideration if the study design requires ongoing, remote access to the data. Yet surprisingly we have been contacted by researchers who only thought about extracting data after their study was complete (luckily we do offer a solution to retroactively retrieve Garmin data).
Are you going to run your study remotely, or connect the devices to your computer manually? If so, are you sure you can even access the files with a manual connection? While most vendors provide a free application programming interface (API) for software developers to access user data, and some provide an additional API or software development kit (SDK) to access more features (usually for a charge), the downside is that you will have to hire your own developer. Apple’s ResearchKit, for example, is a software framework for those who want to build their own app.
For Garmin devices, Labfront offers a no-code solution that collects the data from all of your participants’ devices in one centralized dashboard, where you can also track their adherence. Setting up your project is quick and there is a free version available to test it out.
Fitabase is another research platform primarily used for aggregating and analyzing data from Fitbit devices.
There you have it! We hope our guide can help you select the right wearable device for your study needs. To sum it up, here’s a chart comparing some of the most popular devices right now:
For further reading, we recommend taking a look at this evaluation framework, as well as these considerations from the ePRO Consortium.
Looking for more info on how to get started with wearables?
We offer a free course giving you a comprehensive introduction to using wearables for biomarker date collection in your research.
Alix doubles as the marketing and pun specialist at Labfront. She usually operates quietly behind the scenes, but give her a karaoke mic and all bets are off.