scholarly journals Accelerometry-Based Step Count Validation for Horse Movement Analysis During Stall Confinement

2021 ◽  
Vol 8 ◽  
Author(s):  
Samantha L. Steinke ◽  
Julia B. Montgomery ◽  
John M. Barden

Quantitative tracking of equine movement during stall confinement has the potential to detect subtle changes in mobility due to injury. These changes may warn of potential complications, providing vital information to direct rehabilitation protocols. Inertial measurement units (IMUs) are readily available and easily attached to a limb or surcingle to objectively record step count in horses. The objectives of this study were: (1) to compare IMU-based step counts to a visually-based criterion measure (video) for three different types of movements in a stall environment, and (2) to compare three different sensor positions to determine the ideal location on the horse to assess movement. An IMU was attached at the withers, right forelimb and hindlimb of six horses to assess free-movement, circles, and figure-eights recorded in 5 min intervals and to determine the best location, through analysis of all three axes of the triaxial accelerometer, for step count during stall confinement. Mean step count difference, absolute error (%) and intraclass correlation coefficients (ICCs) were determined to assess the sensor's ability to track steps compared to the criterion measure. When comparing sensor location for all movement conditions, the right-forelimb vertical-axis produced the best results (ICC = 1.0, % error = 6.8, mean step count difference = 1.3) followed closely by the right-hindlimb (ICC = 0.999, % error = 15.2, mean step count difference = 1.8). Limitations included the small number of horse participants and the lack of random selection due to limited availability and accessibility. Overall, the findings demonstrate excellent levels of agreement between the IMU's vertical axis and the video-based criterion at the forelimb and hindlimb locations for all movement conditions.

2020 ◽  
Author(s):  
Jiangang Sun ◽  
Yang Liu

BACKGROUND An increasing number of wrist-worn wearables are being examined in the context of health care. However, studies of their use during physical education (PE) lessons remain scarce. OBJECTIVE We aim to examine the reliability and validity of the Fizzo Smart Bracelet (Fizzo) in measuring heart rate (HR) in the laboratory and during PE lessons. METHODS In Study 1, 11 healthy subjects (median age 22.0 years, IQR 3.75 years) twice completed a test that involved running on a treadmill at 6 km/h for 12 minutes and 12 km/h for 5 minutes. During the test, participants wore two Fizzo devices, one each on their left and right wrists, to measure their HR. At the same time, the Polar Team2 Pro (Polar), which is worn on the chest, was used as the standard. In Study 2, we went to 10 schools and measured the HR of 24 students (median age 14.0 years, IQR 2.0 years) during PE lessons. During the PE lessons, each student wore a Polar device on their chest and a Fizzo on their right wrist to measure HR data. At the end of the PE lessons, the students and their teachers completed a questionnaire where they assessed the feasibility of Fizzo. The measurements taken by the left wrist Fizzo and the right wrist Fizzo were compared to estimate reliability, while the Fizzo measurements were compared to the Polar measurements to estimate validity. To measure reliability, intraclass correlation coefficients (ICC), mean difference (MD), standard error of measurement (SEM), and mean absolute percentage errors (MAPE) were used. To measure validity, ICC, limits of agreement (LOA), and MAPE were calculated and Bland-Altman plots were constructed. Percentage values were used to estimate the feasibility of Fizzo. RESULTS The Fizzo showed excellent reliability and validity in the laboratory and moderate validity in a PE lesson setting. In Study 1, reliability was excellent (ICC>0.97; MD<0.7; SEM<0.56; MAPE<1.45%). The validity as determined by comparing the left wrist Fizzo and right wrist Fizzo was excellent (ICC>0.98; MAPE<1.85%). Bland-Altman plots showed a strong correlation between left wrist Fizzo measurements (bias=0.48, LOA=–3.94 to 4.89 beats per minute) and right wrist Fizzo measurements (bias=0.56, LOA=–4.60 to 5.72 beats per minute). In Study 2, the validity of the Fizzo was lower compared to that found in Study 1 but still moderate (ICC>0.70; MAPE<9.0%). The Fizzo showed broader LOA in the Bland-Altman plots during the PE lessons (bias=–2.60, LOA=–38.89 to 33.69 beats per minute). Most participants considered the Fizzo very comfortable and easy to put on. All teachers thought the Fizzo was helpful. CONCLUSIONS When participants ran on a treadmill in the laboratory, both left and right wrist Fizzo measurements were accurate. The validity of the Fizzo was lower in PE lessons but still reached a moderate level. The Fizzo is feasible for use during PE lessons.


2019 ◽  
Vol 33 (5) ◽  
pp. 936-942 ◽  
Author(s):  
Jayne Lesley Anderson ◽  
L Samantha Yoward ◽  
Angela J Green

Objective: To determine the validity of the ActiGraph GT3X accelerometer in step count quantification when compared to observed step count in hospitalised adults recovering from critical illness. Setting: Large National Health Service (NHS) Hospitals Trust. Subjects: In total, 20 hospital ward-based adults (age: mean 62.3, SD 11.5) who had required greater than 48 hours of mechanical ventilation in the intensive care unit. Main measures: Participants walked self-selected distances and speeds as part of a semi-structured movement protocol not exceeding 3 hours. Two ActiGraph GT3X accelerometers were worn, one on the thigh and one on the ankle of the non-dominant leg. Accelerometer-recorded step counts were compared against observed step counts. Results: In total, 31 separate walking episodes were analysed. A mean (SD) of 45.87 (±19.72) steps was calculated for observed step count (range 15–90). Mean differences (95% limits of agreement) of −0.84 steps (−3.88 to 2.2) for the ankle placement and −17.7 steps (−40.63 to 5.25) for the thigh were calculated. Intraclass correlation coefficients (95% confidence intervals) of 0.99 (0.99 to 1.0) and 0.46 (−0.1 to 0.78) were determined for the ankle and thigh, respectively. Placement sites were well tolerated by 95% of participants. Conclusion: An ankle-mounted ActiGraph GT3X accelerometer demonstrates validity in quantification of step count in hospitalised adults recovering from critical illness. A thigh placement was not considered valid.


Life ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 104
Author(s):  
Lisa Mohr ◽  
Lutz Vogt ◽  
Jan Wilke

During dynamic ultrasound assessments, unintended transducer movement over the skin needs to be prevented as it may bias the results. The present study investigated the validity of two methods quantifying transducer motion. An ultrasound transducer was moved on a pre-specified 3 cm distance over the semitendinosus muscle of eleven adults (35.8 ± 9.8 years), stopping briefly at intervals of 0.5 cm. Transducer motion was quantified (1) measuring the 2-D displacement of the shadow produced by reflective tape (RT) attached to the skin and (2) using a marker-based, three-dimensional movement analysis system (MAS). Differences between methods were detected with Wilcoxon tests; associations were checked by means of intraclass correlation coefficients (ICC 3.1) and Bland–Altman plots. Values for RT (r = 0.57, p < 0.001) and MAS (r = 0.19, p = 0.002) were significantly higher than true distances (TD). Strong correlations were found between RT and TD (ICC: 0.98, p < 0.001), MAS and TD (ICC: 0.95, p < 0.001), and MAS and RT (ICC: 0.97, p < 0.001). Bland–Altman plots showed narrow limits of agreement for both RT (−0.49 to 0.13 cm) and MAS (−0.49 to 0.34 cm) versus TD. RT and MAS are valid methods to quantify US transducer movement. In view of its low costs and complexity, RT can particularly be recommended for application in research and clinical practice.


10.2196/17699 ◽  
2020 ◽  
Vol 8 (8) ◽  
pp. e17699
Author(s):  
Jiangang Sun ◽  
Yang Liu

Background An increasing number of wrist-worn wearables are being examined in the context of health care. However, studies of their use during physical education (PE) lessons remain scarce. Objective We aim to examine the reliability and validity of the Fizzo Smart Bracelet (Fizzo) in measuring heart rate (HR) in the laboratory and during PE lessons. Methods In Study 1, 11 healthy subjects (median age 22.0 years, IQR 3.75 years) twice completed a test that involved running on a treadmill at 6 km/h for 12 minutes and 12 km/h for 5 minutes. During the test, participants wore two Fizzo devices, one each on their left and right wrists, to measure their HR. At the same time, the Polar Team2 Pro (Polar), which is worn on the chest, was used as the standard. In Study 2, we went to 10 schools and measured the HR of 24 students (median age 14.0 years, IQR 2.0 years) during PE lessons. During the PE lessons, each student wore a Polar device on their chest and a Fizzo on their right wrist to measure HR data. At the end of the PE lessons, the students and their teachers completed a questionnaire where they assessed the feasibility of Fizzo. The measurements taken by the left wrist Fizzo and the right wrist Fizzo were compared to estimate reliability, while the Fizzo measurements were compared to the Polar measurements to estimate validity. To measure reliability, intraclass correlation coefficients (ICC), mean difference (MD), standard error of measurement (SEM), and mean absolute percentage errors (MAPE) were used. To measure validity, ICC, limits of agreement (LOA), and MAPE were calculated and Bland-Altman plots were constructed. Percentage values were used to estimate the feasibility of Fizzo. Results The Fizzo showed excellent reliability and validity in the laboratory and moderate validity in a PE lesson setting. In Study 1, reliability was excellent (ICC>0.97; MD<0.7; SEM<0.56; MAPE<1.45%). The validity as determined by comparing the left wrist Fizzo and right wrist Fizzo was excellent (ICC>0.98; MAPE<1.85%). Bland-Altman plots showed a strong correlation between left wrist Fizzo measurements (bias=0.48, LOA=–3.94 to 4.89 beats per minute) and right wrist Fizzo measurements (bias=0.56, LOA=–4.60 to 5.72 beats per minute). In Study 2, the validity of the Fizzo was lower compared to that found in Study 1 but still moderate (ICC>0.70; MAPE<9.0%). The Fizzo showed broader LOA in the Bland-Altman plots during the PE lessons (bias=–2.60, LOA=–38.89 to 33.69 beats per minute). Most participants considered the Fizzo very comfortable and easy to put on. All teachers thought the Fizzo was helpful. Conclusions When participants ran on a treadmill in the laboratory, both left and right wrist Fizzo measurements were accurate. The validity of the Fizzo was lower in PE lessons but still reached a moderate level. The Fizzo is feasible for use during PE lessons.


2018 ◽  
Vol 42 (5) ◽  
pp. 518-526 ◽  
Author(s):  
Elisa S Arch ◽  
Jaclyn M Sions ◽  
John Horne ◽  
Barry A Bodt

Background: Step counts, obtained via activity monitors, provide insight into activity level in the free-living environment. Accuracy assessments of activity monitors are limited among individuals with lower-limb amputations. Objectives: (1) To evaluate the step count accuracy of both monitors during forward-linear and complex walking and (2) compare monitor step counts in the free-living environment. Study design: Cross-sectional study. Methods: Adult prosthetic users with a unilateral transtibial amputation were equipped with StepWatch and FitBit One™. Participants completed an in-clinic evaluation to evaluate each monitor’s step count accuracy during forward linear and complex walking followed by a 7-day step count evaluation in the free-living environment. Results: Both monitors showed excellent accuracy during forward, linear walking (intraclass correlation coefficients = 0.97–0.99, 95% confidence interval = 0.93–0.99; percentage error = 4.3%–6.2%). During complex walking, percentage errors were higher (13.0%–15.5%), intraclass correlation coefficients were 0.88–0.90, and 95% confidence intervals were 0.69–0.96. In the free-living environment, the absolute percentage difference between monitor counts was 25.4%, but the counts had a nearly perfect linear relationship. Conclusion: Both monitors accurately counted steps during forward linear walking. StepWatch appears to be more accurate than FitBit during complex walking but a larger sample size may confirm these findings. FitBit consistently counted fewer steps than StepWatch during free-living walking. Clinical relevance The StepWatch and FitBit are acceptable tools for assessing forward, linear walking for individuals with transtibial amputation. Given the results’ consistenty in the free-living enviorment, both tools may ultimiately be able to be used to count steps in the real world, but more research is needed to confirm these findings.


2014 ◽  
Vol 65 (1) ◽  
pp. 29-34 ◽  
Author(s):  
David Landry ◽  
An Tang ◽  
Jessica Murphy-Lavallée ◽  
Luigi Lepanto ◽  
Jean-Sébastien Billiard ◽  
...  

Purpose Retrospective assessment of impact of cholecystectomy, age, and sex on bile duct (BD) diameter. Materials and Methods We retrospectively reviewed abdominal contrast-enhanced multidetector computed tomography and laboratory reports of 290 consecutive patients (119 men; mean age, 55.9 years) who presented without cholestasis to the emergency department of our institution between June 2009 and August 2010. BD diameters were measured in 3 locations, by 2 independent observers, twice, at 1-month intervals. Reproducibility and agreement were evaluated by intraclass correlation coefficients and Bland-Altman analyses. The effects of cholecystectomy, age, and sex on BD diameter were analysed with linear mixed models. Results BD diameter inter-reader reproducibility and agreement were excellent at the level of the right hepatic artery (intraclass correlation coefficient, 0.94). Sixty-one patients (21.0%) had a history of cholecystectomy. Among them, the 95th percentile of BD diameters at hepatic artery level was 7.9 mm (<50 years) and 12.3 mm (≥50 years). Among those without cholecystectomy, BD diameter was 6.2 mm (<50 years) and 7.7 mm (≥50 years). Cholecystectomy was associated with significantly larger BD diameters in both age groups ( P < .001). Older age was associated with larger BD diameters ( P = .004). Sex had no impact on BD diameter ( P = .842). Conclusion Patients after cholecystectomy may present with an enlarged BD unrelated to cholestasis. The BD diameter increases with age. Clinicians should rely on cholecystectomy status, age, and laboratory results to determine needs of further investigation.


2012 ◽  
Vol 36 (2) ◽  
pp. 159-164 ◽  
Author(s):  
Yoon Tae Kim ◽  
Jung Soo Lee

Background: Each plantar pressure measurement system has a different accuracy and reliability, which is required to establish a range of normal values and determine the reliability. Objectives: To determine normal pressures with the Gaitview® system and assess its reliability. Study Design: Single-group repeated measures. Methods: Dynamic barefoot plantar pressure data were obtained in 30 healthy young participants. In each session, three trials were recorded by one examiner for each foot using the two-step gait initiation method, which was repeated by another examiner the same day. One week later, all of the procedures were repeated. Time-integral mean pressures were measured for each of eight anatomical foot regions. The foot contact time (CT) and the time-integral mean angle of the center of pressure (COP) were also measured. Results: The greatest time-integral mean pressures were seen under the medial and lateral heel. The mean CT was 0.9 sec for both feet, and the time-integral mean angle of the COP was 9.3° for the right foot and 6.6° for the left. The intraclass correlation coefficients (ICCs) ranged from 0.69 to 0.97, and the coefficient of variation (CoV) from 9.9 to 59.97% for all parameters. Conclusions: These findings indicate that the Gaitview® system demonstrates good to moderate reliability. Clinical relevance The Gaitview® AFA-50 system (alFOOTs, Seoul, Republic of Korea) has been used by clinicians in Korea, but has not been investigated in an independent study. Therefore, this study established a range of normal values and determined the reliability of the Gaitview® AFA-50 system.


2021 ◽  
Vol 4 (1) ◽  
pp. 89-95
Author(s):  
Bronwyn Clark ◽  
Elisabeth Winker ◽  
Matthew Ahmadi ◽  
Stewart Trost

Accurate measurement of time spent sitting, standing, and stepping is important in studies seeking to evaluate interventions to reduce sedentary behavior. In this study, the authors evaluated the agreement in classification of these activities from three algorithms applied to thigh-worn ActiGraph accelerometers using predictions from the widely used activPAL device as a criterion. Participants (n = 29, 72% female, age 23–68 years) wore the activPAL3™ micro (processed by PAL software, version 7.2.32) and the ActiGraph™ GT9X accelerometer on the right front thigh concurrently for working hours on one full workday (7.2 ± 1.2 hr). ActiGraph output was classified via the three test algorithms: ActiGraph’s ActiLife software (inclinometer); an open source method; and, a machine-learning algorithm reported in the literature (Acti4). Performance at an instance level was evaluated by computing classification accuracy (F scores) for 15-s windows. The F scores showed high accuracy relative to the criterion for identifying sitting (96.7–97.1) and were 84.7–85.1 for identifying standing and 78.1–80.6 for identifying stepping. The four methods agreed strongly in total time spent sitting, standing, and stepping, with intraclass correlation coefficients of .96 (95% confidence interval [.92, .96]), .92 (95% confidence interval [.81, .96]), and .87 (95% confidence interval [.53, .95]) but sometimes overestimated sitting time and underestimated standing time relative to activPAL. These algorithms for identifying sitting, standing, and stepping from thigh-worn accelerometers provide estimates that are very similar to those obtained using the activPAL.


2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Marjolaine Baude ◽  
Emilie Hutin ◽  
Jean-Michel Gracies

Objective. To design a bidimensional facial movement measuring tool and study its reliability.Methods. We utilized the free video-analysis software Kinovea that can track preselected points during movements and measure two-point distances off-line. Three raters positioned facial markers on 10 healthy individuals and video-taped them during maximal bilateral contractions of frontalis, corrugator, orbicularis oculi, zygomaticus, orbicularis oris, and buccinator, on two occasions. Each rater also analyzed the first video twice, one week apart. For each muscle, intrarater reliability was measured by percent agreements (PA) and intraclass correlation coefficients (ICC) between two assessments of the same video one week apart and between assessments of two videos collected one week apart. Interrater reliability was measured by PA, ICC, and coefficients of variation (CV) between assessments of the first video-recording by the three raters.Results. Intrarater and interrater reliabilities were good to excellent for frontalis (PA and ICC > 70%; CV < 15%), moderate for orbicularis oculi, zygomaticus, and orbicularis oris, and poor for corrugator and buccinators.Discussion. Without formal prior training, the proposed method was reliable for frontalis in healthy subjects. Improved marker selection, training sessions, and testing reliability in patients with facial paresis may enhance reliability for orbicularis oculi, zygomaticus, and orbicularis oris.


1991 ◽  
Vol 34 (5) ◽  
pp. 989-999 ◽  
Author(s):  
Stephanie Shaw ◽  
Truman E. Coggins

This study examines whether observers reliably categorize selected speech production behaviors in hearing-impaired children. A group of experienced speech-language pathologists was trained to score the elicited imitations of 5 profoundly and 5 severely hearing-impaired subjects using the Phonetic Level Evaluation (Ling, 1976). Interrater reliability was calculated using intraclass correlation coefficients. Overall, the magnitude of the coefficients was found to be considerably below what would be accepted in published behavioral research. Failure to obtain acceptably high levels of reliability suggests that the Phonetic Level Evaluation may not yet be an accurate and objective speech assessment measure for hearing-impaired children.


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