Skip to main content
. 2021 Jun 3;9(6):e25138. doi: 10.2196/25138

Table 2.

Summary of devices used, ordered by the year of publication.

Studies and devices Devices, sensors, measurement Purpose
Najafi et al (2010) [44] Wearable: hip-worn strap (prototypea)

  • Triaxial ACCb (quaternions)

  • Triaxial gyroscope (quaternions)

  • Triaxial magnetometer (quaternions)

Complementary: pressure platform (Emed-x system, Novel Inc)

  • Pressure sensor (area of sway)

 Recognize the motion of ankle and hip joints in 3 dimensions
Grewal et al (2013) [56] Wearable: lower limb band (LEGSys, BioSensics LLC)

  • ACC (acceleration)

  • Gyroscope (angular velocity)

 Gait detection
Luštrek et al (2014) [36] Smartphone (model not specified)

  • ACC (acceleration)

Wearable: chest strap (model not specified)

  • ACC (acceleration)

  • HRMc (HRd)

 Smartphone location detection; activity recognition: walking, running, cycling, lying, sitting, and standing; and energy expenditure estimation
Luštrek et al (2015) [37] Smartphone (model not specified)

  • ACC (acceleration, location, HR, and RRe)

  • Microphone (sound)

  • GPS (location and velocity)

  • Wi-Fi (location)

Wearable: chest strap (model not specified)

  • ACC (acceleration)

  • ECGf (HR and RR)

 Activity recognition: sleep, exercise, work, transport, eating, home, and outdoor
Cvetković et al (2016) [47] Smartphone (model not specified)

  • ACC (acceleration)

  • Microphone (sound)

  • GPS (location and velocity)

  • Wi-Fi (location)

Wearable: chest strap (model not specified)

  • ACC (acceleration)

  • ECG (HR and RR)

 Activity recognition: sleep, exercise, work, transport, eating, home, and out
Calbimonte et al (2017) [38] Wearable: chest strap (Bioharness 3, Zephyr)

  • ACC (acceleration)

  • ECG (HBg fiducial points location, STh segment shape, QTci interval, HR, and RR)

 Generate 2 semantic models: physiological and energy expenditure for classifying hypoglycemic events
Fraiwan et al (2017) [48] Smartphone (Samsung Galaxy S6 Edge Plus, Samsung)
Complementary: infrared thermal camera (FLIR ONE, FLIR Systems, Inc)

  • Infrared sensor (thermal images)

  • Camera (standard image)

 Recognize change of temperature on the feet
McLean et al (2017) [49] Smartphone (model not specified)

  • ACCs (acceleration)

  • GPS (location)

  • Wi-Fi (location)

  • Camera (photo)

  • Magnetometer (magnetic field strength)

  • Bluetooth (physical proximity)

 Quantify physical proximity, sedentary behavior, vehicle use, and location
Razjouyan et al (2017) [57] Wearable: chest strap (Bioharness 3, Zephyr)

  • ACC (acceleration)

  • ECG (HR, RR, and core body temperature)

 Detection of physiological stress of the patient
Reddy et al (2017) [39] Smartphone (Nexus 5, LG Corporation and Google, LLC)

  • Camera and flash (PPGj)

Complementary: peripheral pulse oximeter (model not specified)

  • Pulse oximeter (PPG)

 Discriminate between diabetic and healthy individuals
Turksoy et al (2017) [50] Wearable: armband (SenseWear, BodyMedia)

  • ACC (acceleration)

  • Thermometer (skin temperature and near-body temperature)

  • Galvanometer (galvanic skin response)

  • Heat flux (rate of heat dissipating from the body)

Wearable: CGM (Guardian Real-Time, Medtronic)

  • GMk (GLl)

Wearable: CGM (Dexcom G4 Platinum, Dexcom, Inc)

  • GM (GL)

Wearable: chest strap (Bioharness 3, Zephyr)

  • ACC (acceleration)

  • ECG (HR)

Wearable: smartwatch (Mio Alpha, MIO Global)

  • HRM (HR)

Complementary: open-circuit spirometry metabolic cart system (True One, Parvo Medics)

  • Expired gases (O2 and CO2)

 Find a correlation between biometric changes and glucose concentrations during exercise
Bartolic et al (2018) [40] Smartphone (model not specified)

  • App (insulin doses)

Wearable: wristband (Fitbit fitness bracelet, Fitbit, Inc)

  • ACC (acceleration)

  • HRM (HR)

Complementary: glucometer (Contour Next One, Ascensia Diabetes Care)

  • GM (GL)

 Quantify physical activity, daily movement, sleep duration and quality, calorie consumption, insulin dosages, and continuous GL
Faccioli et al (2018) [45] Smartphone (model not specified)

  • App (carbohydrates count)

Wearable: activity tracker (model not specified)

  • ACC (acceleration)

Wearable: CGM (model not specified)

  • GM (continuous GL)

 Quantify step count, continuous GL, and carbohydrate intake
Groat et al (2018) [51] Smartphone (model not specified)

  • App (exercise behavior)

Wearable: wristband (Fitbit Charge HR, Fitbit, Inc)

  • HRM (HR)

Wearable: CGM (Enlite, Medtronic)

  • GM (continuous GL)

 Quantify exercise behavior measured via a wristband and an app to compare with the rate of change in GL recorded by a CGM
McMillan et al (2018) [46] Wearable: thigh-worn (activPAL, PAL Technologies Ltd)

  • ACC (acceleration)

  • Inclinometer (acceleration)

Wearable: FGM (FreeStyle Libre, Abbott Diabetes Care)

  • GM (continuous GL)

 Quantify step count, cadence and postural transitions and energy expenditure estimates, and continuous GL
Merickel et al (2018) [32] Wearable: wristwatch (model not specified)

  • ACC (acceleration)

  • HRM (HR)

Wearable: CGM (Dexcom G4 Platinum, Dexcom, Inc)

  • GM (continuous GL)

Complementary: vehicle sensor instrumentation packages (model not specified)

  • Camera (video)

  • GPS (vehicle acceleration and speed)

  • OBDm sensor (vehicle acceleration and speed)

 Compare the driving behavior from drivers with and without T1Dn
Nguyen Gia et al (2019) [41] Wearable: chest strap (prototype)

  • ACC (acceleration)

  • Gyroscope (angular velocity)

  • Magnetometer (magnetic field)

  • ECG (QTo intervals and HR)

  • GM (continuous GL)

  • Thermometer (body temperature)

Complementary: ambient sensors (prototype)

  • Ambient sensor (room temperature, humidity, and air quality)

 Monitor DMp and ECG, and report abnormalities: fall, very low or high GL, and abnormal HR in real time without interfering with the patient’s daily activities
Rescio et al (2019) [33] Wearable: smart insole (prototype)

  • Infrared thermometer (plantar temperature)

  • Pressure sensor (pressure)

 Monitor temperature and pressure of the plantar foot
Sarda et al (2019) [52] Smartphone (model not specified)

  • ACC (acceleration)

  • Call logs (communication)

  • GPS (location)

  • Ambient light sensor (ambient light)

 Activity recognition: mobility, sleep, and social interaction 
Ramazi et al (2019) [34] Wearable: CGM (Dexcom G4 Platinum, Dexcom, Inc)

  • GM (continuous GL)

Wearable: wristband (model not specified; ActiGraph, ActiGraph LLC)

  • ACC (acceleration)

 Quantify GL, traveled steps, and physical activity: sitting, standing, and lying
Garcia et al (2019) [35] Smartphone (iPhone 7, Apple Inc)

  • Camera (standard image)

 Capture facial images
Sevil et al (2019) [42] Wearable: wristband (Empatica E4, Empatica Inc)

  • ACC (acceleration)

  • PPG (blood volume pulse)

  • Galvanometer (galvanic skin response)

  • Infrared thermopile (skin temperature)

Wearable: CGM (Dexcom G5, Dexcom, Inc)

  • GM (continuous GL)

 Estimate acute psychological stress effect index and GL
Zherebtsov et al (2019) [43] Wearable: wristband (AMT-LAZMA 1, Aston Medical Technology Ltd)

  • Laser Doppler flowmetry (Doppler shift)

 Quantify changes in the microcirculatory blood flow in tissues
Rodriguez-Rodriguez et al (2019) [53] Wearable: FGM (FreeStyle Libre, Abbott Diabetes Care)

  • GM (continuous GL)

 Quantify GL for the creation of a database for further processing by the prediction models
Sanz et al (2019) [54] Wearable: wristband (Fitbit Charge HR, Fitbit, Inc)

  • ACC (acceleration)

  • HRM (HR)

  • Altimeter (altitude)

Wearable: wristband (Microsoft Band 2, Microsoft Corporation)

  • HRM (HR)

  • Skin temperature (skin temperature)

  • Galvanometer (galvanic skin response)

  • ACC (acceleration)

Wearable: wristband (Polar RCX3, Polar Electro)

  • HRM (HR)

Wearable: CGM (Enlite-2, Medtronic Minimed)

  • GM (continuous GL)

Complementary: glucose and L-lactate analyzer (YSI 2300 Stat Plus Glucose Analyzer, YSI Incorporated Life Sciences)

  • GM (GL)

 Quantify number of steps walked, number of floors of stairs climbed, exercise intensity, calories burned, and skin electrodermal activity
Whelan et al (2019) [55] Wearable: wristband (Fitbit Charge 2, Fitbit, Inc)

  • ACC (acceleration)

  • Altimeter (altitude)

  • HRM (HR)

Wearable: wristband (ActiGraph wGT3x-BT, ActiGraph LLC)

  • ACC (acceleration)

Wearable: FGM (FreeStyle Libre, Abbott Diabetes Care)

  • GM (continuous GL)

 Quantify number of steps walked, distance traveled, HR, calories expended, flights of stairs climbed, and GL

aText in italic represents model and company of each devices in that order. In the cases of no specification on the correspondent manuscript “Model not specified” it is stated.

bACC: accelerometer.

cHRM: heart rate monitor.

dHR: heart rate.

eRR: respiration rate.

fECG: electrocardiogram.

gHB: heartbeat.

hST: electrocardiogram measurement ST interval.

iQTc: corrected electrocardiogram measurement QT interval.

jPPG: photoplethysmogram.

kGM: glucose monitor.

lGL: glucose level.

mOBD: on-board diagnostics device.

nT1D: type 1 diabetes.

oQT: electrocardiogram measurement QT interval.

pDM: diabetes mellitus.