TABLE 1.
Comparative Assessment of Logistical and Functional Characteristics of Polar H10 and Bittium Faros™
| Characteristics | Polar H10https://www.polar.com/en/sensors | Bittium Faros™https://www.bittium.com/medical/bittium-faros/ |
|---|---|---|
| Recorded parameters | Heart rate and RR intervals. Raw ECG data capture is possible but needs a live connection to an external device through Polar’s Bluetooth Low Energy (BLE) Software Development Kit (SDK) |
Medical grade ECG: records the complete ECG waveform |
| Sampling rate | 1,000 Hz | 125–1,000 Hz (adjustable) |
| Accessories needed | A chest strap A smartwatch and mobile app for data recording and transfer |
A chest strap with adaptor or electrodes A USB cable or a smartphone for data transfer |
| Maximal memory capacity in offline recording) | 95,000 RR intervals (~20 hours) | 4GB (~93 days of continuous single-channel ECG recording and ~32 days for 3 channels of ECG data, sampled at 250 Hz with 16-bit resolution) |
| Maximal battery autonomy | 6 days, 3–4 days for the smartphone | 14 days for the sensor, 3–4 days for the smartphone |
| Accessibility for purchase/rent | Online | Through medical institutions or Bittium’s direct sales channel |
| Purchase cost | ~$100 USD | $1,000–$4,000 USD for the device and the smartphone |
| Additional costs | $350–$850 USD for the smartwatch. | $85 USD for the chest strap with adaptor and cable for data transfer |
| Rental cost | Cannot be rented | $100–$150 USD/ month Chest strap with adaptor and cable for data transfer need to be purchased separately |
| Software/app needed for data recording | Polar Beat mobile app on a paired smartphone is necessary for recording HR data. Polar Flow used with a smartwatch or a third-party app is necessary to store RR data. | The sensor comes with a manager software, enabling to setup recording preferences. After the recording data from the sensor can be download in EDF format. CardioFlex® app is helpful to preregister sensors (see below) |
| Specificities of data recording | A trained researcher should control the app activation and device pairing and manually starting and stopping recording session for each participant. Researchers should ensure that participants do not attempt to operate the device independently. | Sensors preregistered on CardioFlex® Recording parameters can be defined on CardioFlex® A trained researcher and a computer are needed to start and stop the device recording |
| Software/app/devices necessary for data transfer | A smartwatch with Polar Flow or a smartphone with Polar Beat app and permanent Bluetooth connection | Data is transferred by connecting the sensor directly to a computer via USB |
| Specificities of data transfer | The sensor and mobile device should be kept close (max 10 m) to not lose Bluetooth connection. The app needs strong enough background permissions, to not be shut down by mobile operating services. |
The smartphone allows automatic data transfer to Cardiac Navigator™. It is enough to put the sensor next to the smartphone once a day to transfer the data. |
| Advantages/disadvantages of data transfer modalities for occupational studies | During the measurement, study participants need to carry either a smartwatch, which they may not be allowed to wear, or a mobile device with an app, which might be impossible to install on professional IT equipment. | Internal memory capacity of the sensor is 4GB Study participants do not need to carry the smartphone during their work shift. |
| Data storage platform | Polar Flow | Bittium Medical Suite (online platform) |
| Specificities of data storage | A Polar Flow account can store up to 5 participants data and needs an email address. An e-mail can be linked to max 5 accounts. The participants need to be carefully labeled or have their own account. |
Link between each participant’s account on CardioFlex® (Bittium Medical Suite) and Cardiac Navigator™ (analytics environment) |
| Data available for extraction | RR intervals | Complete ECG waveform |
| Software/application necessary for data extraction | Polar Flow | Cardiac Navigator™ |
| Extracted file format | Training Center XML (TCX), CSV | European Data Format (EDF), ie, binary file format for storing multichannel time-series data and |
| Software/applications necessary for data management and analysis | Several commercial and open-sources programs and web-based applications (eg, Kubios HRV; Nevrokard aHRV, RHRV) | Several commercial and open-sources programs and web-based applications (eg, Kubios HRV; Nevrokard aHRV and LT-HRV, Bittium Cardiac Navigator™, and Cardiaoscope™, RHRV) |
| Undesirable health effects | Potential mild skin irritation due to the chest strap | Potential mild skin irritation due to the chest strap or the electrodes |
| What could affect data quality | The chest strap moving Participant clothing | The chest strap moving and participant clothing, however, the use of electrode patches avoids this issue. |
ECG, electrocardiogram; CSV, comma-separated values; EDF, European Data Format; HR, heart rate; HRV, heart rate variability; IT, Information Technology; LT-HRV, long-term heart rate variability; RHRV, R heart rate variability; RR interval, beat-to-beat time interval in ECG; USB, Universal Serial Bus.