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Table 2 Characteristics of studies included in the scoping review

From: Smartwatches in healthcare medicine: assistance and monitoring; a scoping review

Author/century

Study design

Participant/Subject

Aim/Objective

Result/Outcome

Stress monitoring

 Muhammad Ali Fauzi's et al. (2022) [1]

/ Norway

Experimental

15 participants

Compared three learning strategies for stress detection tasks

The experiment involved using smartwatches to collect physiological data, create classifiers, and monitor the stress levels of hospital staff in real time

 Morales A et al. (2022) [2]

/ Brazil

Systematic Review

38 articles

The aim of the study is to develop a stress surveillance system that can help individuals manage their stress levels and improve their quality of life

The study identified several physicochemical parameters that can be used to monitor stress levels, including heart rate variation, cortisol analysis, skin conductance, body temperature, and blood volume at the wrist. The article concludes that developing a wrist wearable for stress identification using physiological and chemical sensors is challenging but possible and applicable

 Muhammad Ali Fauzi's et al. (2021) [3]

/ Norway

Experimental

Seven machine learning methods

This study proposed a method for detecting continuous stress using single classifiers and classifier ensembles

It was found that single classifiers had the best accuracy, LR had the best precision, and NN had the best recall for stress detection

 Vila G et al. (2019) [4]

/ France

Experimental

1604 workers

The study focuses on developing a system that monitors passengers' stress levels during air travel and provides real-time feedback to cabin crew

The study's outcome is a proof-of-concept for a real-time stress monitoring system that can improve passengers' experience during air travel

 Han HJ et al. (2020) [5]

/ United State America (USA)

Experimental

17 participants

The study focuses on developing a system that can monitor physiological and behavioural data, including heart rate, skin conductance, and facial expressions, to estimate stress levels

The outcome of the study is a proof-of-concept for a stress monitoring system that can be used in everyday settings to improve the user's well-being

 Gjoreski M et al. (2020) [6]

/ Slovenia

Experimental

23 participants

  

 Francisco de Arriba Pérez et al. (2018) [7]/ Spain

Experimental

12 Students

This study proposes a protocol to evaluate solutions based on commercial-off-the-shelf (COTS) wrist wearables to estimate student stress

The protocol was carried out in two phases: an initial laboratory-based stress induction test and a monitoring stage in the classroom while the student performs academic activities

Movement disorders

 Syed Mustafa Ali et al. (2021) [8]

/ United Kingdom (UK)

Longitudinal observational study

Fifty-three individuals

Examined the longitudinal engagement of users of a smartwatch app in people living with MLTC-M, stratifying engagement patterns by age, gender, number of disease domains and question type

This study suggests that people living with MLTC-M can use smartwatches to report multiple symptoms per day and that this data could be integrated into electronic health records to support clinical care

 Amiri et al. (2017) [9]

/ USA

Feasibility study

12 healthy subjects aged 23 to 33 years (165 samples were collected)

And two subjects aged 15 and 16

developed an Internet-of-Things (IoT) framework called WearSense that uses the sensory capabilities of modern smartwatches to detect stereotypic behaviours in children with autism

This study used a smartwatch to record motion data and develop a system to detect and monitor autistic behavioural activities. The system had an accuracy of 96.7% in detecting three autistic actions

 Juan C. Torrado's et a. (2017)[10]

/ Spain

Experimental

Two people with autism disorder

This study focused on using smartwatches to help people with autism spectrum disorders with emotion regulation problems

They found that the smartwatch can help individuals with alexithymia and emotional dysregulation control their stress episodes triggered by various stimuli, except for the learning phase of the experiment

 Stephen A et al. (2019) [11]

/ USA

Experimental; accelerometer data

They recruited 20 older adults

They tested whether a smartphone or smartwatch could detect whether an older adult was walking with or without an assistive device

They found that smartwatches provided much higher quality data for detecting walkers and canes compared to smartphones and that a second sensor on the hip was required for the user-generated classifiers to make the most accurate predictions

 Tchuente, Franck et al. (2020) [12]/ Canada

Experimental

They recruited 30 able-bodied people (15 male, 15 female)

In this study, smartwatches are used to classify aggressive movements, which could benefit care providers in settings where people suffer from movement disorders

The kNN and ReliefF combination demonstrated that this smartwatch-based approach is a viable solution for identifying aggressive behavior and could be used by care providers in settings where people suffer from dementia or mental health disorders, where random aggressive behaviors often occur

Sleep tracking

 Chen et al. (2021) [13]

/ China

Experimental

20 subjects

In this study, ApneaDetector was developed as a smartwatch-based system to detect sleep apnoea

The study found that while the ApneaDetector accurately classified normal and sleep apnoea events, it had problems with more specific categorisations such as OSA, CSA, and hypopnoea

 Chen et al. (2021) [14]

/ China

Experimental

20 patients

A pilot study was conducted to analyze the effectiveness of a smartwatch with seven sensors in screening for Obstructive Sleep Apnea (OSA). The study generated respiratory waveforms and detected sleep–wake states using PPG (photoplethysmography) signals

PPG-based smartwatches were more effective than simultaneous in-lab PSG or HSAT devices when screening suspected cases of OSA

 Mehrabadi et al. (2020) [15]

/ USA

Experimental

45 healthy individuals

This study investigated the accuracy of sleep data from the Oura ring compared to medically approved actigraphy devices in 45 healthy individuals aged between 18 and 55

The results revealed that the Oura ring was significantly more accurate than the Samsung Gear Sport smartwatch in detecting heart rate, sleep, and activity parameters

Blood pressures

 Falter et al. (2022) [16]

/ Belgium

Prospective, single-arm, cross-sectional study

40 patients

Consecutive patients scheduled for 24-h ambulatory blood pressure monitoring were recruited from the cardiology outpatient clinic

This study has found that the Samsung Galaxy Watch Active 2 has an anchoring point when calibrating the device, resulting in an overestimation of lower blood pressures (BPs) and an underestimation of higher BPs. This indicates that the smartwatch is not ready for clinical usage due to its systematic bias toward a certain calibration point

 Mark Tsou et al. (2021) [17]

/ Taiwan

Experimental

49 subjects

This study examined the applicability of smartwatches in PM2.5 health assessment

The results indicated that the elevated PM2.5 concentration was significantly associated with G-HR for low-intensity activities and marginally associated with G-HR for moderate- to high-intensity activities

 Yen et al. (2022) [18]

/ Taiwan

A randomised controlled trial (RCT)

adults aged 20–65

This study was conducted as a single-blinded, two-arm study to test the effectiveness of a commercial smartwatch with a BP-monitoring feature

This study demonstrates that using a smartwatch with BP-monitoring features can improve blood pressure and other health parameters, increase awareness of high blood pressure, and modify related risk factors

Heart disease

 Bumgarner et al. (2018) [19]/ USA

A prospective, nonrandomised, and adjudicator-blinded study

100 patients

This was a non-randomized study in that the accuracy of the KB automated algorithm was evaluated by comparing its results to physician-interpreted KB rhythm strips and simultaneous ECGs

Physician interpretation of KB tracings produced by smartwatches demonstrated similar results in testing with 99% sensitivity, 83% specificity, and a K coefficient of 0.83. This suggests that the quality of KB tracings produced by smartwatches is highly reliable and accurate

 Liao et al. (2022) [20]

/ Taiwan

Randomised

116 patients

This study evaluated the accuracy of the AF detection algorithm by obtaining ECG waveforms and PPG signals from patients undergoing AF catheter ablation while considering other arrhythmias' impact on it

Results suggest that using a longer length (25-beat) for analysing PPG data leads to higher accuracy in discriminating AF from SR compared to using only 10 beats

Covid pandemic

 Abbasi et al. (2020) [21]

/ USA

 

333 participants

In this study, researchers analysed data collected from 333 participants who used the DETECT smartphone app to enter symptoms and test results

The model analysed both symptoms and sensor data, and the results showed that the distinction between positive and negative cases was more accurate

 Niela-Vilén et al. (2021) [22]/ Finland

A longitudinal cohort study design

38 pregnant women

This longitudinal cohort study investigated the use of an Internet of Things (IoT)-based system and smartwatch technology for monitoring pregnant women

The findings of this study showed that the pandemic-related restrictions were associated with increased heart rate variability, stress levels, decreased physical activity, and decreased sleep duration

 Hunter et al. (2022) [23]

/

Great Britain or UK

Multicenter Observational Study

mean age of 57 years

In the study, Fitbit Charge 3 watches were given to each participant to follow up on their complications after the recovered disease

This study demonstrated that smartwatches can monitor physical activity remotely

 Mishra T et al. (2020) [24]

/ USA

Cohort

5,262 participants

This study explored whether wearable devices could detect COVID-19 at an early, pre-symptomatic stage

It was determined that abnormal physiological events, such as elevated resting heart rate and increased heart rate relative to the number of steps, can be detected using a smartwatch at or near the time of infection

 Quer et al. (2022) [25]

/ USA

Cohort

7298 volunteers

This study hypothesised that there are digital, objective biomarkers of reactogenicity that could be identified by detecting subtle deviations from an individual's normal resting heart rate

They demonstrated that it is possible to detect physiologic manifestations of reactogenicity to COVID-19 vaccination through individual changes in RHR

 Guan G et al. (2022) [26]

/ USA

Cohort

1534 participants

This study uses the Garmin Vivosmart 4 smartwatch to measure heart rate and heart rate variability

This study showed that smartwatches are more accurate than patients' self-reports in predicting post-vaccination physiological conditions

Safety

 Lacour P et al. (2020) [27]

/ Germany

Single case

148 patients

This prospective observational study evaluated the potential for electromagnetic interference with CIEDs

This study shows that there is no risk of EMIs between the iPhone and CIEDs, but relatively frequent telemetry interferences do occur between the iPhone and the CIEDs

 Tzeis S et al. (2021) [28]

/ Greece

Cohort

171 patients

This prospective, multicenter study was conducted to investigate whether the use of the latest generation smartwatches might interfere with the proper functioning of the CIED

The emission levels of the tested smartwatches and their magnetic chargers were evaluated by measuring low-frequency magnetic fields between 110 and 400 kHz

 Fischer et al. (2022) [29]

/ Switzerland

Prospective comparative

13 different settings

This study evaluated a popular smartwatch for its ability to monitor noise levels in 13 occupational and recreational settings accurately

Smartwatch accuracy was lower in settings with rapid acoustic fluctuations but comparable to the sound level meter across different pressure levels based on SD of LAeq differences and ICC results

Validations or evaluation

 Pope et al. (2019) [30]

/ USA

 

21 healthy college students

This study examined four popular smartwatches' validity, measurement bias, and precision in assessing EE, average HR, and peak HR during active play

This study suggested that smartwatches should not be used as part of a systems medicine approach to health care

 Shenglong et al. (2022) [31]

/ China

 

20 healthy Chinese participants

This study measured individual VE, VO2 and VCO2 using the Cosmed K5 system for a wide range of metabolic rates

The findings of this study indicate that smartwatches may have moderate validity in estimating energy expenditure for outdoor walking and running

 Sarhaddi et al. (2022) [32]

/ Finland

Observational study

28 healthy individuals

This study evaluated the validity of the Samsung Gear Sport smartwatch in terms of HR and HRV parameters compared with a medical-grade chest ECG monitor in a 24-h continuous free-live setting monitoring

The smartwatch can accurately measure HR and HRV parameters during sleep and awake time and provide acceptable RMSSD, SDNN, LF, and HF

 Brew B et al. (2022) [33]

/ Australia

Cross-sectional study

22 volunteer participants

This study used a threshold-based algorithm programmed for different smartwatches to detect a fall on 22 volunteer participants automatically

This study found that an algorithm programmed in commercially available smartwatches to detect induced falls had an overall sensitivity of 77% and specificity of 99%. The fall detection performance depends on the algorithm used, and the sensitivity ranges from 70 to 100% and the specificity from 80 to 100%, depending on the type of fall. In addition, they showed that the performance of a fall detection algorithm could be strongly dependent on the smartwatch model

 Auepanwiriyakul et al. (2020) [34]

/ UK

Combined methods design

15 healthy volunteers

This study evaluated raw IMU sensor data quality, followed by a trial of the feasibility of wearable health devices in a clinical environment

In this study, wearable IMU technology, such as smartwatches and research-grade IMU Xsens, was cleaner linear acceleration signals and fewer errors than Axivity due to additional magnetometer and strap-down integration technology. This technology is viewed positively by healthcare professionals, according to this study on its acceptability among hospital patients

 Varghese et al. (2021) [35]

/ Germany

Prospective study

400 participants

This study was a prospective study from 2018 to the end of 2021, in which they recruited and measured the hand movements of 400 participants using Apple smartwatches and smartphones. The aim was to distinguish PD from other movement disorders and healthy individuals

Results showed that smartwatches had high agreement with seismological sensor validation in measuring movement subtleties or hand-tremor amplitudes and frequencies more accurately than clinical documentation or human vision