Validation of a 3D Camera System for Cycling Analysis

Background: Kinematic analysis aimed toward scientific investigation or professional purposes is commonly unaffordable and complex to use. Objective: The purpose of this study was to verify concurrent validation between a cycling-specific 3D camera and the gold-standard 3D general camera systems. Methods: Overall, 11 healthy amateur male triathletes were filmed riding their bicycles with Vicon 3D cameras and the Retul 3D cameras for bike fitting analysis simultaneously. All 18 kinematic measurements given by the bike fitting system were compared with the same data given by Vicon cameras through Pearson correlation (r), intraclass correlation coefficients (ICC), standard error measurements (SEM), and Bland–Altman (BA) analysis. Confidence intervals of 95% are given. Results: A very high correlation between cameras was found on six of 18 measurements. All other presented a high correlation between cameras (between 0.7 and 0.9). In total, six variables indicate a SEM of less than one degree between systems. Only two variables indicate a SEM higher than two degrees between camera systems. Overall, four measures indicate bias tendency according to BA. Conclusions: The cycling-specific led-emitting 3D camera system tested revealed a high or very high degree of correlation with the gold-standard 3D camera system used in laboratory motion capture. In total, 14 measurements of this equipment could be used in sports medicine clinical practice and even by researchers of cycling studies.

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Reproducibility and Validity of the 10-Meter Shuttle Ride Test in Wheelchair-Using Children and Adolescents With Cerebral Palsy

Physical Therapy ◽

10.2522/ptj.20120513 ◽

2013 ◽

Vol 93 (7) ◽

pp. 967-974 ◽

Cited By ~ 29

Author(s):

Olaf Verschuren ◽

Maremka Zwinkels ◽

Marjolijn Ketelaar ◽

Femke Reijnders-van Son ◽

Tim Takken

Keyword(s):

Cerebral Palsy ◽

Cardiorespiratory Fitness ◽

Gold Standard ◽

Pearson Correlation ◽

Intraclass Correlation ◽

Correlation Coefficients ◽

Peak Oxygen Uptake ◽

Repeated Measurements ◽

Manual Wheelchair ◽

Intraclass Correlation Coefficients

BackgroundFor children with cerebral palsy (CP) who are able to walk or run, the 10-m shuttle run test is currently the test of choice to assess cardiorespiratory fitness. This test, however, has not yet been examined in wheelchair-using youth with CP.ObjectiveThe purpose of this study was to investigate the test-retest reproducibility and validity of the 10-m shuttle ride test (SRiT) in youth with CP.DesignRepeated measurements of the SRiT were obtained.MethodsTwenty-three individuals with spastic CP (18 boys, 5 girls; mean age=13.3 years, SD=3.6 years) using a manual wheelchair for at least part of the day participated in this study. During the study, all participants performed one graded arm exercise test (GAET) and 2 identical SRiTs within 2 weeks. Peak oxygen uptake (V̇o2peak), peak heart rate (HRpeak), and respiratory exchange ratio (RER) were recorded. Intraclass correlation coefficients (2,1), the smallest detectable difference, and the limits of agreement (LOA) were calculated. The association between the results of the SRiT and GAET was tested using Pearson correlation coefficients.ResultsIntraclass correlation coefficients (.99, 95% confidence interval=.98–1.00) for all variables indicated highly acceptable reproducibility. The LOA analysis revealed satisfactory levels of agreement. The SRiT variables demonstrated strong, significant positive correlations for V̇o2peak values obtained during the SRiT and the GAET (r=.84, P<.01).LimitationsAlthough the GAET is considered the gold standard, the cardiorespiratory demand during the GAET was significantly lower compared with during the SRiT. Future studies should determine whether the GAET can still be accepted as the gold standard for upper-extremity exercise.ConclusionsThe SRiT is a reproducible and valid test for measuring cardiorespiratory fitness in youth with spastic CP who self-propel a manual wheelchair.

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Utility of 1 Measurement Versus Multiple Measurements of Near Point of Convergence After Concussion

Journal of Athletic Training ◽

10.4085/1062-6050-431-19 ◽

2020 ◽

Vol 55 (8) ◽

pp. 850-855

Author(s):

Nathan Ernst ◽

Philip Schatz ◽

Alicia M. Trbovich ◽

Kouros Emami ◽

Shawn R. Eagle ◽

...

Keyword(s):

Sports Medicine ◽

Clinical Utility ◽

Clinical Care ◽

Pearson Correlation ◽

Intraclass Correlation ◽

Correlation Coefficients ◽

Physical Symptoms ◽

Common Finding ◽

Neurocognitive Performance ◽

Distance Measurements

Context Increased near point of convergence (NPC) distance is a common finding after concussion and is associated with physical symptoms and worsened neurocognitive performance. Vestibular/Ocular Motor Screening measures NPC distance across 3 trials and uses the average measurement to inform clinical care. However, whether 3 trials are necessary, are consistent, or add clinical utility is unknown. Objective To investigate the consistency across 3 trials of NPC and establish the classification accuracy (ie, clinical utility) of 1 or 2 trials compared with the standardized average of 3 trials. Design Retrospective cohort study. Setting Sports medicine clinic and research laboratory. Patients or Other Participants Consecutively enrolled patients aged 10 to 22 years with diagnosed concussions (74% sport related; n = 380). Main Outcome Measure(s) The previously reported clinical cutoff value of ≥5 cm across 3 trials was used. Pearson correlation and intraclass correlation coefficients were used to evaluate agreement between trials and average scores. Reliable change indices (RCIs) using 95% confidence intervals were also calculated. Results The Pearson correlation (r = .98) and intraclass correlation (0.98) coefficients revealed excellent agreement between the first measurement and average NPC distance across 3 measurements. The RCI across all trials was 2 cm. When the first NPC measurement was ≤3 cm or ≥7 cm, agreement existed within the RCI between the first measurement and the average of 3 measurements in 99.6% of cases. When we averaged the first and second measurements, 379/380 (99.7%) participants had the same classification (ie, <5 cm = normal, ≥5 cm = abnormal) as the average NPC distance across 3 measurements. Conclusions Our findings suggest limited utility of multiple or average NPC distance measurements when the initial NPC distance is outside of RCI clinical cutoffs (ie, ≤3 cm or ≥7 cm). Given the high consistency between the first measurement and average NPC distance across 3 trials, only 1 measurement of NPC distance is warranted unless the first measurement is between 3 and 7 cm.

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Eyelid Measurements: Smartphone-Based Artificial Intelligence-Assisted Prediction (Preprint)

10.2196/preprints.32444 ◽

2021 ◽

Author(s):

Hung-Chang Chen ◽

Shin-Shi Tzeng ◽

Yen-Chang Hsiao ◽

Ruei-Feng Chen ◽

Erh-Chien Hung ◽

...

Keyword(s):

Artificial Intelligence ◽

Image Processing ◽

Gold Standard ◽

Human Error ◽

Pearson Correlation ◽

Intraclass Correlation ◽

Correlation Coefficients ◽

Processing Algorithm ◽

Image Processing Algorithm ◽

Predicted Values

BACKGROUND Margin reflex distance 1(MRD1), margin reflex distance 2 (MRD2), and levator muscle function (LF) are crucial for ptosis evaluation and management. Manual measurements of MRD1, MRD2, and LF are time-consuming, subjective, and prone to human error. Smartphone-based artificial intelligence (AI) image processing is a potential solution to overcome these limitations. OBJECTIVE We proposed the first smartphone-based AI-assisted image processing algorithm for MRD1, MRD2, and LF measurements. METHODS This observational study included 822 eyes of 411 volunteers aged over 18 years from August 1, 2020, to April 30, 2021. Six orbital photographs (bilateral primary gaze, up-gaze, and down-gaze) were taken using a smartphone (iPhone 11 pro max). The gold standard measurements and normalized eye photographs were obtained from these orbital photographs and compiled using AI-assisted software to create MRD1, MRD2 and LF models. RESULTS The Pearson correlation coefficients between the gold standard measurements and the predicted values obtained with the MRD1 and MRD2 models were excellent (r = 0.91, and 0.88, respectively) and with the LF model were good (r = 0.73). The intraclass correlation coefficient results showed excellent agreement between the gold standard measurements and the values predicted by the MRD1and MRD2 models (0.90, and 0.84, respectively), and substantial agreement with the LF model (0.69). The mean absolute errors were 0.35 mm, 0.37 mm, and 1.06 mm for MRD1, MRD2, and LF models, respectively. The 95% limits of agreement were -0.94 to 0.94 mm for the MRD1 model; -0.92 to 1.03 mm for the MRD2 model; and -0.63 to 2.53 mm for the LF model. CONCLUSIONS In this study, we proposed the first smartphone-based AI-assisted image processing algorithm for eyelid measurements. MRD1, MRD2, and LF measures can be taken in a quick, objective, and convenient manner. Furthermore, by using a smartphone, the examiner can check these measurements anywhere and at any time, which facilitates data collection.

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A Quantitative Comparison of Multispectral Refraction Topography and Autorefractometer in Young Adults

Frontiers in Medicine ◽

10.3389/fmed.2021.715640 ◽

2021 ◽

Vol 8 ◽

Author(s):

Yunru Liao ◽

Zhenlan Yang ◽

Zijing Li ◽

Rui Zeng ◽

Jing Wang ◽

...

Keyword(s):

Correlation Coefficient ◽

Pearson Correlation ◽

Intraclass Correlation ◽

Correlation Coefficients ◽

Cross Sectional Study ◽

Cross Sectional ◽

High Agreement ◽

Intraclass Correlation Coefficients ◽

Repeatability And Reproducibility ◽

The Mean

Purpose: Purpose of this study is to evaluate the measuring consistency of central refraction between multispectral refraction topography (MRT) and autorefractometry.Methods: This was a descriptive cross-sectional study including subjects in Sun Yat-sen Memorial Hospital from September 1, 2020, to December 31, 2020, ages 20 to 35 years with a best corrected visual acuity of 20/20 or better. All patients underwent cycloplegia, and the refractive status was estimated with autorefractometer, experienced optometrist and MRT. We analyzed the central refraction of the autorefractometer and MRT. The repeatability and reproducibility of values measured using both devices were evaluated using intraclass correlation coefficients (ICCs).Results: A total of 145 subjects ages 20 to 35 (290 eyes) were enrolled. The mean central refraction of the autorefractometer was −4.69 ± 2.64 diopters (D) (range −9.50 to +4.75 D), while the mean central refraction of MRT was −4.49 ± 2.61 diopters (D) (range −8.79 to +5.02 D). Pearson correlation analysis revealed a high correlation between the two devices. The intraclass correlation coefficient (ICC) also showed high agreement. The intrarater and interrater ICC values of central refraction were more than 0.90 in both devices and conditions. At the same time, the mean central refraction of experienced optometrist was −4.74 ± 2.66 diopters (D) (range −9.50 to +4.75D). The intra-class correlation coefficient of central refraction measured by MRT and subjective refraction was 0.939.Conclusions: Results revealed that autorefractometry, experienced optometrist and MRT show high agreement in measuring central refraction. MRT could provide a potential objective method to assess peripheral refraction.

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An investigation into the validity and reliability of the Chinese version of Spinal Cord Independence Measure III (SCIM III)

Clinical Rehabilitation ◽

10.1177/0269215520966703 ◽

2020 ◽

pp. 026921552096670

Author(s):

Huayi Xing ◽

Nan Liu ◽

Fin Biering-Sørensen

Keyword(s):

Spinal Cord ◽

Spinal Cord Injury ◽

Barthel Index ◽

Pearson Correlation ◽

Intraclass Correlation ◽

Correlation Coefficients ◽

Chinese Version ◽

Validity And Reliability ◽

Post Injury ◽

Cord Injury

Objective: To investigate the validity and reliability of a Chinese version of Spinal Cord Independence Measure III (SCIM III) in individuals with spinal cord injury. Design: Study on psychometric properties. Setting: An inpatient rehabilitation facility in China. Subjects: 102 participants with spinal cord injury. Mean (SD) age was 48.8 (15.6) years; tetraplegia/paraplegia ratio was 50/52; median time post injury was 2 months. Intervention: SCIM III was translated into Chinese. Chinese versions of Barthel Index and SCIM III were filled out for each participant by Rater 1. SCIM III was then administered by Rater 2 after 24 hours ( n = 67) and 7 days ( n = 65). Main Measures: Validity, inter-rater/test-retest reliability, and internal consistency of the Chinese version of SCIM III. Results: The total scores between the two raters were similar (mean ± SD: 33.8 ± 25.8 vs 33.8 ± 25.5, P = 0.95). Total agreement between the raters in each item was >80%, with both Pearson and intraclass correlation coefficients >0.97 ( P < 0.01) for each subscale and total score. The Pearson correlation coefficients of the two independent assessments performed by Rater 2 were also >0.97 ( P < 0.01) for each subscale and the total score. Cronbach α was >0.7 for each subscale and the total score for both raters. High consistency was found between Barthel Index and SCIM III total scores (Pearson correlation coefficient = 0.88, P < 0.01). Conclusion: The Chinese version of SCIM III is valid and reliable for the functional assessment of patients with SCI.

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A Comparative Study of Clinical vs. Digital Exophthalmometry Measurement Methods

Journal of Ophthalmology ◽

10.1155/2020/1397410 ◽

2020 ◽

Vol 2020 ◽

pp. 1-6

Author(s):

Tháıs de Sous Pereira ◽

Cristina Hiromi Kuniyoshi ◽

Cristiane de Almeida Leite ◽

Eloisa M. M. S. Gebrim ◽

Mário L. R. Monteiro ◽

...

Keyword(s):

Ct Scan ◽

Pearson Correlation ◽

Intraclass Correlation ◽

Correlation Coefficients ◽

Measurement Methods ◽

Gold Standard Method ◽

Mean Values ◽

Ct Measurements ◽

Mean Differences ◽

No Gold Standard

Background. A number of orbital diseases may be evaluated based on the degree of exophthalmos, but there is still no gold standard method for the measurement of this parameter. In this study we compare two exophthalmometry measurement methods (digital photography and clinical) with regard to reproducibility and the level of correlation and agreement with measurements obtained with Computerized Tomography (CT) measurements. Methods. Seventeen patients with bilateral proptosis and 15 patients with normal orbits diseases were enrolled. Patients underwent orbital CT, Hertel exophthalmometry (HE) and standardized frontal and side facial photographs by a single trained photographer. Exophthalmometry measurements with HE, the digital photographs and axial CT scans were obtained twice by the same examiner and once by another examiner. Pearson correlation coefficient (PCC) was used to assess correlations between methods. Validity between methods was assessed by mean differences, interintraclass correlation coefficients (ICC’s), and Bland–Altman plots. Results. Mean values were significantly higher in the proptosis group (34 orbits) than in the normal group (30 orbits), regardless of the method. Within each group, mean digital exophthalmometry measurements (24.32 ± 5.17 mm and 18.62 ± 3.87 mm) were significantly greater than HE measurements (20.87 ± 2.53 mm and 17.52 ± 2.67 mm) with broader range of standard deviation. Inter-/intraclass correlation coefficients were 0.95/0.93 for clinical, 0.92/0.74 for digital, and 0.91/0.95 for CT measurements. Correlation coefficients between HE and CT scan measurements in both groups of subjects (r = 0.84 and r = 0.91, p<0.05) were greater than those between digital and CT scan measurements (r = 0.61 and r = 0.75, p<0.05). On the Bland–Altman plots, HE showed better agreement to CT measurements compared to the digital photograph method in both groups studied. Conclusions. Although photographic digital exophthalmometry showed strong correlation and agreement with CT scan measurements, it still performs worse than and is not as accurate as clinical Hertel exophthalmometry. This trail is registered with NCT01999790.

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Assessing the Motor Status Score: A Scale for the Evaluation of Upper Limb Motor Outcomes in Patients after Stroke

Neurorehabilitation and Neural Repair ◽

10.1177/154596830201600306 ◽

2002 ◽

Vol 16 (3) ◽

pp. 283-289 ◽

Cited By ~ 56

Author(s):

Mark Ferraro ◽

Jennifer Hogan Demaio ◽

Jennifer Krol ◽

Chris Trudell ◽

Keren Rannekleiv ◽

...

Keyword(s):

Correlation Coefficient ◽

Upper Limb ◽

Pearson Correlation ◽

Intraclass Correlation ◽

Correlation Coefficients ◽

Pearson Correlation Coefficient ◽

Maximum Score ◽

Intraclass Correlation Coefficients ◽

Upper Extremity Impairment ◽

Motor Outcomes

The Motor Status Scale (MSS) measures shoulder, elbow (maximum score = 40), wrist, hand, and finger movements (maximum score = 42), and expands the measurement of upper extremity impairment and disability provided by the Fugl-Meyer (FM) score. This work examines the interrater reliability and criterion validity of the MSS performed in patients admitted to a rehabilitation hospital 21 ± 4 days after stroke. Using the MSS and the FM, 7 occupational therapists masked to each other’s judgments, evaluated 12 consecutive patients with stroke. Two therapists evaluated 6 additional patients on consecutive days. Intraclass correlation coefficients were significant for each group of raters for the shoulder/elbow and for the wrist/hand (P < 0.0001); test-retest measures were also significant for the shoulder/elbow (Pearson correlation coefficient r = 0.99, P < 0.004) and for the wrist/hand (Pearson correlation coefficient r = 0.99, P < 0.003). The internal item consistency for the overall MSS was significant (Cronbach alpha = 0.98, P < 0.0001). Finally the correlation between the MSS and the FM (R 2 = 0.964) was significant (P < 0.0001). The MSS affords a reliable and valid assessment of upper limb impairment and disability following stroke.

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The Validity of In Vivo Tooth Volume Determinations From Cone-Beam Computed Tomography

The Angle Orthodontist ◽

10.2319/121608-639.1 ◽

2010 ◽

Vol 80 (1) ◽

pp. 160-166 ◽

Cited By ~ 47

Author(s):

Yi Liu ◽

Raphael Olszewski ◽

Emanuel Stefan Alexandroni ◽

Reyes Enciso ◽

Tianmin Xu ◽

...

Keyword(s):

Computed Tomography ◽

Cone Beam Computed Tomography ◽

Interobserver Reliability ◽

Pearson Correlation ◽

Intraclass Correlation ◽

Correlation Coefficients ◽

Volumetric Analysis ◽

Cone Beam ◽

Water Displacement

Abstract Objective: To determine the accuracy of volumetric analysis of teeth in vivo using cone-beam computed tomography (CBCT). Materials and Methods: The physical volume (Vw) of 24 bicuspids extracted for orthodontic purposes (16 were imaged with the I-CAT and 8 with the CB MercuRay) were determined using the water displacement technique. Corresponding pretreatment CBCT image data were uploaded into Amira 4.0 for segmentation and radiographic volume (Va). All measurements were performed twice by two observers. The statistical difference between Vw and Va was assessed using a paired t-test. The intraobserver and interobserver reliability were determined by calculating Pearson correlation coefficients and intraclass correlation coefficients. Results: The overall mean Vw of teeth specimens was 0.553 ± 0.082 cm3, while the overall mean Va was 0.548 ± 0.079 cm3 (0.529 ± 0.078 cm3 for observer 1 and 0.567 ± 0.085 cm3 for observer 2). There were statistically significant differences between Va and Vw (P < .05). Between observer 1 and observer 2, Va measurements were statistically significantly different (P < .05). The interobserver and intraobserver correlation coefficient for Vw was high. Lastly, surface smoothing reduced the volume by 3% to 12%. Conclusions: In vivo determination of tooth volumes from CBCT data is feasible. The measurements slightly deviate from the physical volumes within −4% to 7%. Smoothing operations reduce volume measurements. Currently, no requirements for accuracy of volumetric determinations of tooth volume have been established.

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Development and Validation of MRI Sacroiliac Joint Scoring Methods for the Semiaxial Scan Plane Corresponding to the Berlin and SPARCC MRI Scoring Methods, and of a New Global MRI Sacroiliac Joint Method

The Journal of Rheumatology ◽

10.3899/jrheum.161583 ◽

2017 ◽

Vol 45 (1) ◽

pp. 70-77 ◽

Cited By ~ 10

Author(s):

Pernille Hededal ◽

Mikkel Østergaard ◽

Inge Juul Sørensen ◽

Anne Gitte Loft ◽

Jens S. Hindrup ◽

...

Keyword(s):

Sacroiliac Joint ◽

Controlled Trial ◽

Linear Regression Analysis ◽

Intraclass Correlation ◽

Correlation Coefficients ◽

Scoring Methods ◽

Double Blind ◽

Smallest Detectable Change ◽

Observed Score ◽

Very High

Objective.To develop semiaxial magnetic resonance imaging (MRI) scoring methods for assessment of sacroiliac joint (SIJ) bone marrow edema (BME) in patients with axial spondyloarthritis, and to compare the reliability with equivalent semicoronal scoring methods.Methods.Two semiaxial SIJ MRI scoring methods were developed based on the principles of the semicoronal Berlin and Spondyloarthritis Research Consortium of Canada (SPARCC) methods. A global quadrant-based method was also developed. Baseline and 12-week MRI of the SIJ from 51 patients participating in a randomized double-blind placebo-controlled trial of adalimumab 40 mg every other week versus placebo were scored by the semiaxial and the corresponding semicoronal methods. Results were compared by linear regression analysis. The reproducibility and sensitivity were evaluated by intraclass correlation coefficients (ICC) and smallest detectable change [SDC, absolute values and percentage of the highest observed score (SDC-HOS)].Results.Interreader and intrareader ICC were moderate to very high for semiaxial scoring methods (baseline 0.83–0.88 and 0.85–0.97; change 0.33–0.78), while high to very high for semicoronal scoring methods (baseline 0.90–0.92 and 0.93–0.97; change 0.77–0.89). Association between semiaxial and semicoronal scores were high for both the Berlin and SPARCC method (baseline: R2 = 0.93 and 0.88; change: R2 = 0.82 and 0.87, respectively), while lower for the global method (baseline: R2 = 0.79; change: R2 = 0.54). The SDC-HOS were 9.8–18.6% and 5.9–10.7% for the semiaxial and semicoronal methods, respectively.Conclusion.Detection of SIJ BME in the semiaxial scan plane is feasible and reproducible. However, a slightly lower reliability of all 3 semiaxial methods supports the general practice of using the coronal scan-plane in therapeutic studies.

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Reliability and concurrent validity of an alternative method of lateral lumbar range of motion in athletes

South African Journal of Sports Medicine ◽

10.17159/2078-516x/2016/v28i1a1414 ◽

2016 ◽

Vol 28 (1) ◽

pp. 23-26 ◽

Cited By ~ 1

Author(s):

M Hecimovich

Keyword(s):

Lumbar Spine ◽

Range Of Motion ◽

Concurrent Validity ◽

Pearson Correlation ◽

Intraclass Correlation ◽

Correlation Coefficients ◽

Index Test ◽

Low Back ◽

Detectable Change ◽

Rater Reliability

Background: Cricket bowling involves combined spinalmovements of side bending and rotation and, consequently, injuryto the low back is a common problem. Therefore the assessmentof lumbar spine kinematics has become a routine component inpreseason screening. This includes static measurement of lateralspinal flexion as asymmetrical range of motion may predispose anathlete to low back injury.Objectives: This study examined intra-rater reliability andconcurrent validity of the fingertip-to-floor distance test (FFD)when compared to a criterion range of motion measure.Methods: Thirty-four junior-level cricket players aged 13‑16years were recruited. Lumbar spine lateral flexion was measuredsimultaneously with the fingertip-to-floor distance test and digitalinclinometry methods. Relative and absolute intra-rater reliabilitywere investigated with intraclass correlation coefficients (ICC3,1)of agreement, standard error of measurement (SEM) estimates,Bland and Altman bias estimates and 95% limits of agreement,respectively. The concurrent validity of the fingertip-to-floordistance test, compared to digital inclinometry measures, wasexamined with Pearson correlation coefficients.Results: Intra-rater reliability demonstrated substantial agreementfor both measures (ICC3,1 > 0.84). The fingertip-to-floor distancetest SEM values ranged from 1.71‑2.01 cm with an estimatedminimum detectable change (MDC) threshold of 4.73‑5.55 cm.The inclinometry SEM values ranged from 1.00‑1.09° withminimal detectable change estimates of 2.77‑3.01°. There werestrong correlations between the index test and criterion measureoutcomes (r > 0.84, p < 0.001).Conclusions: This study’s results support the intra-rater reliabilityand concurrent validity of the finger-to-floor distance test,suggesting it to be a suitable surrogate measure for lumbar lateralflexion testing

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