scholarly journals Acceleration of 2D-MR fingerprinting by reducing the number of echoes with increased in-plane resolution: a volunteer study

2020 ◽  
Vol 33 (6) ◽  
pp. 783-791
Author(s):  
Yusuke Yokota ◽  
Tomohisa Okada ◽  
Yasutaka Fushimi ◽  
Akira Yamamoto ◽  
Satoshi Nakajima ◽  
...  
Keyword(s):  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Region Of Interest ◽  
Intraclass Correlation Coefficients ◽  
Coefficients Of Variation ◽  
Volunteer Study ◽  
The Mean ◽  
T1 And T2 ◽  
High Repeatability ◽  
Measurement Repeatability

Abstract Objective To compare the absolute values and repeatability of magnetic resonance fingerprinting (MRF) with 3000 and 1500 echoes/slice acquired in 41 s and 20 s (MRF3k and MRF1.5k, respectively). Materials and methods MRF3k and MRF1.5k scans based on fast imaging with steady precession (FISP) were conducted using a 3 T scanner. Inter-scan agreement and intra-scan repeatability were investigated in 41 and 28 subjects, respectively. Region-of-interest (ROI) analysis was conducted on T1 values of MRF3k by two raters, and their agreement was evaluated using intraclass correlation coefficients (ICCs). Between MRF3k and MRF1.5k, differences in T1 and T2 values and inter-measurement correlation coefficients (CCs) were investigated. Intra-measurement repeatability was evaluated using coefficients of variation (CVs). A p value < 0.05 was considered statistically significant. Results The ICCs of ROI measurements were 0.77–0.96. Differences were observed between the two MRF scans, but the CCs of the overall ROIs were 0.99 and 0.97 for the T1 and T2 values, respectively. The mean and median CVs of repeatability were equal to or less than 1.58% and 3.13% in each of the ROIs for T1 and T2, respectively; there were some significant differences between MRF3k and MRF1.5k, but they were small, measuring less than 1%. Discussion Both MRF3k and MRF1.5k had high repeatability, and a strong to very strong correlation was observed, with a trend toward slightly higher values in MRF1.5k.

Is the location of the signal intensity weighted centroid a reliable measurement of fluid displacement within the disc?

2018 ◽  
Vol 63 (4) ◽  
pp. 453-460 ◽  
Author(s):  
Vahid Abdollah ◽  
Eric C. Parent ◽  
Michele C. Battié
Keyword(s):  
Signal Intensity ◽  
Water Distribution ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Region Of Interest ◽  
Rater Reliability ◽  
Fluid Displacement ◽  
Intraclass Correlation Coefficients ◽  
The Mean ◽  
Standard Error Of Measurement

Abstract Degenerated discs have shorter T2-relaxation time and lower MR signal. The location of the signal-intensity-weighted-centroid reflects the water distribution within a region-of-interest (ROI). This study compared the reliability of the location of the signal-intensity-weighted-centroid to mean signal intensity and area measurements. L4-L5 and L5-S1 discs were measured on 43 mid-sagittal T2-weighted 3T MRI images in adults with back pain. One rater analysed images twice and another once, blinded to measurements. Discs were semi-automatically segmented into a whole disc, nucleus, anterior and posterior annulus. The coordinates of the signal-intensity-weighted-centroid for all regions demonstrated excellent intraclass-correlation-coefficients for intra- (0.99–1.00) and inter-rater reliability (0.97–1.00). The standard error of measurement for the Y-coordinates of the signal-intensity-weighted-centroid for all ROIs were 0 at both levels and 0 to 2.7 mm for X-coordinates. The mean signal intensity and area for the whole disc and nucleus presented excellent intra-rater reliability with intraclass-correlation-coefficients from 0.93 to 1.00, and 0.92 to 1.00 for inter-rater reliability. The mean signal intensity and area had lower reliability for annulus ROIs, with intra-rater intraclass-correlation-coefficient from 0.5 to 0.76 and inter-rater from 0.33 to 0.58. The location of the signal-intensity-weighted-centroid is a reliable biomarker for investigating the effects of disc interventions.

scholarly journals An Electromyographic Analysis of the Deep Cervical Flexor Muscles in Performance of Craniocervical Flexion

2003 ◽  
Vol 83 (10) ◽  
pp. 899-906 ◽  
Author(s):  
Deborah Falla ◽  
Gwendolen Jull ◽  
Paul Dall'Alba ◽  
Alberto Rainoldi ◽  
Roberto Merletti
Keyword(s):  
Muscle Activity ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Bipolar Electrodes ◽  
Intraclass Correlation Coefficients ◽  
Reliability Estimates ◽  
Flexor Muscles ◽  
The Mean ◽  
Electromyographic Analysis ◽  
Electromyographic Signals

Abstract Background and Purpose. This study evaluated an electromyographic technique for the measurement of muscle activity of the deep cervical flexor (DCF) muscles. Electromyographic signals were detected from the DCF, sternocleidomastoid (SCM), and anterior scalene (AS) muscles during performance of the craniocervical flexion (CCF) test, which involves performing 5 stages of increasing craniocervical flexion range of motion—the anatomical action of the DCF muscles. Subjects. Ten volunteers without known pathology or impairment participated in this study. Methods. Root-mean-square (RMS) values were calculated for the DCF, SCM, and AS muscles during performance of the CCF test. Myoelectric signals were recorded from the DCF muscles using bipolar electrodes placed over the posterior oropharyngeal wall. Reliability estimates of normalized RMS values were obtained by evaluating intraclass correlation coefficients and the normalized standard error of the mean (SEM). Results. A linear relationship was evident between the amplitude of DCF muscle activity and the incremental stages of the CCF test (F=239.04, df=36, P&lt;.0001). Normalized SEMs in the range 6.7% to 10.3% were obtained for the normalized RMS values for the DCF muscles, providing evidence of reliability for these variables. Discussion and Conclusion. This approach for obtaining a direct measure of the DCF muscles, which differs from those previously used, may be useful for the examination of these muscles in future electromyographic applications.

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

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.

scholarly journals Action Boundary Proximity Effects on Perceptual-Motor Judgments

2019 ◽  
Vol 90 (12) ◽  
pp. 1000-1008
Author(s):  
Caleb D. Johnson ◽  
Alice D. LaGoy ◽  
Gert-Jan Pepping ◽  
Shawn R. Eagle ◽  
Anne Z. Beethe ◽  
...  
Keyword(s):  
Intraclass Correlation ◽  
Reaction Times ◽  
Correlation Coefficients ◽  
Proximity Effects ◽  
Testing Time ◽  
Good Reliability ◽  
Intraclass Correlation Coefficients ◽  
Coefficients Of Variation ◽  
Time Required ◽  
Action Coupling

INTRODUCTION: Designed as a more ecological measure of reaction times, the Perception-Action Coupling Task (PACT) has shown good reliability and within-subject stability. However, a lengthy testing period was required. Perceptual-motor judgments are known to be affected by proximity of the stimulus to the action boundary. The current study sought to determine the effects of action boundary proximity on PACT performance, and whether redundant levels of stimuli, eliciting similar responses, can be eliminated to shorten the PACT.METHODS: There were 9 men and 7 women who completed 4 testing sessions, consisting of 3 familiarization cycles and 6 testing cycles of the PACT. For the PACT, subjects made judgments on whether a series of balls presented on a tablet afford “posting” (can fit) through a series of apertures. There were 8 ratios of ball to aperture size (B-AR) presented, ranging from 0.2 to 1.8, with each ratio appearing 12 times (12 trials) per cycle. Reaction times and judgment accuracy were calculated, and averaged across all B-ARs. Ratios and individual trials within each B-AR were systematically eliminated. Variables were re-averaged, and intraclass correlation coefficients (ICC) and coefficients of variation (CVTE) were calculated in an iterative manner.RESULTS: With elimination of the 0.2 and 1.8 B-ARs, the PACT showed good reliability (ICC = 0.81–0.99) and consistent within-subject stability (CVTE = 2.2–14.7%). Reliability (ICC = 0.81–0.97) and stability (CVTE = 2.6–15.6%) were unaffected with elimination of up to 8 trials from each B-AR.DISCUSSION: The shortened PACT resulted in an almost 50% reduction in total familiarization/testing time required, significantly increasing usability.Johnson CD, LaGoy AD, Pepping G-J, Eagle SR, Beethe AZ, Bower JL, Alfano CA, Simpson RJ, Connaboy C. Action boundary proximity effects on perceptual-motor judgments. Aerosp Med Hum Perform. 2019; 90(12):1000–1008.

Reproducibility of 24-h energy expenditure and macronutrient oxidation rates in an indirect calorimeter

1996 ◽  
Vol 80 (1) ◽  
pp. 133-139 ◽  
Author(s):  
M. D. White ◽  
G. Bouchard ◽  
B. Buemann ◽  
N. Almeras ◽  
J. P. Despres ◽  
...  
Keyword(s):  
Energy Expenditure ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Whole Body ◽  
Tissue Mass ◽  
Intraclass Correlation Coefficients ◽  
Oxidation Rates ◽  
Coefficients Of Variation ◽  
Habitual Diet ◽  
Adipose Tissue Mass

The maintenance of weight and adipose tissue mass in humans appears to be related to a balance between the rates of oxidation and consumption of macronutrients; yet, little evidence is available on the reproducibility of 24-h macronutrient oxidation rates and how this relates to diet in the days preceding a chamber session. This study examined the reproducibility of 24-h macronutrient oxidation rates, 24-h energy expenditure (EE), and respiratory quotient (RQ) in 30 adults who ate their habitual diets before two 24-h whole body indirect calorimeter sessions. Results showed that the within-subject coefficients of variation (CVws) for 24-h EE and RQ were 2.8 and 2.6%, respectively. CVws for macronutrient oxidations ranged from approximately 15 to 25%. Means comparisons of 24-h EE, RQ, and macronutrient oxidation rates between sessions showed no significant differences, and all variables had significant positive intraclass correlation coefficients (P < 0.05). In conclusion, macronutrient oxidations all showed significant reproducibility for the group and a significant but lower reproducibility for individuals when habitual diet and activity preceded the experimental sessions.

Reproducibility of Acoustic Rhinometry in the Investigation of Occupational Rhinitis

2007 ◽  
Vol 21 (4) ◽  
pp. 474-477 ◽  
Author(s):  
Roberto Castano ◽  
Gilles Thériault ◽  
Denyse Gautrin ◽  
Heberto Ghezzo ◽  
Carole Trudeau ◽  
...  
Keyword(s):  
Objective Assessment ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Acoustic Rhinometry ◽  
Nasal Patency ◽  
Cross Sectional ◽  
Occupational Rhinitis ◽  
Intraclass Correlation Coefficients ◽  
Objective Monitoring ◽  
Coefficients Of Variation

Background To diagnose occupational rhinitis, it is mandatory to conduct an objective assessment of changes in nasal patency during specific inhalation challenge (SIC). The reproducibility of acoustic rhinometry measurements in the setting of occupational challenges has never been examined. This study assessed the reproducibility of acoustic rhinometry during SIC investigation of occupational rhinitis. Methods Twenty-four subjects underwent acoustic rhinometry measurements during SIC investigation of occupational rhinitis. Subjects attended 3–6 days of SIC within a week by means of a realistic or closed-circuit apparatus methodology Results All of the within-day intraclass correlation coefficients (ICCs) for nasal volume (2–5 cm) and minimum cross-sectional area (MCA) based on a different number of measurements (2–7) were above 0.85; all of the coefficients of variation (CVs) for the same parameters were low (below 10%). The between-day CVs based on different numbers of SIC sessions ranged from 8.0 to 8.8% and from 6.8 to 8.8% for nasal volume and MCA, respectively. The between-day ICCs ranged from 0.80 to 0.88 and from 0.83 to 0.94 for nasal volume and MCA, respectively. Conclusion Acoustic rhinometry showed good within- and between-day reproducibility and can be recommended for the objective monitoring of nasal patency during SIC investigating occupational rhinitis.

Reliability of Clinical Tests of Foot and Ankle Characteristics in Older People

2003 ◽  
Vol 93 (5) ◽  
pp. 380-387 ◽  
Author(s):  
Hylton B. Menz ◽  
Anne Tiedemann ◽  
Marcella Mun-San Kwan ◽  
Mark Dominic Latt ◽  
Catherine Sherrington ◽  
...  
Keyword(s):  
Older People ◽  
Hallux Valgus ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Foot And Ankle ◽  
Clinical Tests ◽  
First Metatarsophalangeal Joint ◽  
Intraclass Correlation Coefficients ◽  
Coefficients Of Variation ◽  
Severity Grading

Lower-extremity problems are common in older people; however, the reliability of clinical tools used to assess foot and ankle characteristics has not been rigorously evaluated. This study evaluated the test–retest reliability of a battery of simple clinical tests of foot and ankle characteristics (tactile sensitivity of the first metatarsophalangeal joint, navicular height, foot length and width, hallux valgus severity, an overall foot problem score, ankle flexibility, ankle dorsiflexion strength, and foot pain) in 31 individuals (13 men and 18 women) aged 76 to 87 years recruited from the community. Three examiners performed the tests on two occasions approximately 2 weeks apart. Intraclass correlation coefficients and coefficients of variation were calculated for continuously scored tests, and the kappa statistic (κ) was used to determine the reliability of hallux valgus severity grading. All of the continuously scored tests had acceptable reliability (intraclass correlation coefficients of 0.64 to 0.98; coefficients of variation of 0.6% to 15.0%), as did hallux valgus severity grading (κ = 0.77; absolute percentage agreement, 84%). These simple clinical tests can now be used with confidence in clinical and research settings to provide reliable and functionally important information regarding foot and ankle characteristics in older people. (J Am Podiatr Med Assoc 93(5): 380-387, 2003)

scholarly journals Development of a Fitness Test Battery for Special Weapons and Tactics (SWAT) Operators—A Pilot Study

2021 ◽  
Vol 18 (15) ◽  
pp. 7992
Author(s):  
Megan Sax van der Weyden ◽  
Christopher D. Black ◽  
Daniel Larson ◽  
Brian Rollberg ◽  
Jason A. Campbell
Keyword(s):  
Repeated Measures ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Police Departments ◽  
Fitness Test ◽  
Intraclass Correlation Coefficients ◽  
Body Drag ◽  
Testing Measure ◽  
Coefficients Of Variation ◽  
Reliable Testing

This investigation examined relationships between a Special Weapons and Tactics-specific fitness test (SORT) and an obstacle course (OC) used for qualification in fourteen male SWAT members from three local, regional police departments. The SORT included: squat, pushup, and lunge in 60 s; pullup hold; sled drag; and Yo-Yo Intermittent Recovery Test L1. The obstacle course included: 25 m sprint (repeated); window ascent; scale under a wall; 25 m serpentine run (repeated), body drag (20 m, repeated). Pearson coefficients examined SORT and OC relationships (p ≤ 0.05); intraclass correlation coefficients (ICC2,1) assessed agreement of SORT trials. Repeated measures ANOVA evaluated differences in SORT metrics across time. Coefficients of variation (COV) examined SORT scoring consistency. The YoYo test was related to all SORT assessments (r = −0.803–0.894), except sled drag. The remaining SORT metrics were related to ≥two tests. SORT COVs ranged from 0.77–13.26% for trials 1–2 but decreased between trials 2–3 (0.95–8.97%). The OC was associated with YoYo, lunges, squats and sled drag (r = −0.790, −0.730, −0.766, and 0.802, respectively). No differences (p > 0.05) existed across SORT trials for event scores. The SORT battery appears to be a valid and reliable testing measure to assess SWAT occupational specific fitness.

scholarly journals The 10/5 Repeated Jumps Test: Are 10 Repetitions and Three Trials Necessary?

Biomechanics ◽  
2020 ◽  
Vol 1 (1) ◽  
pp. 1-14
Author(s):  
Callum Stratford ◽  
Thomas Dos’Santos ◽  
John J. McMahon
Keyword(s):  
Repeated Measures ◽  
Intraclass Correlation ◽  
Force Plate ◽  
Correlation Coefficients ◽  
Pairwise Comparisons ◽  
Strength Index ◽  
Intraclass Correlation Coefficients ◽  
Coefficients Of Variation ◽  
Repeated Measures Analysis ◽  
Ground Contact Time

The purpose of this study was to identify whether ten repetitions and three trials were necessary to achieve stability in peak reactive strength index (RSI) during the 10/5 repeated jumps test (RJT). Twenty-five males, from multiple sports, performed three trials of the RJT on an in-ground force plate, with 90 seconds’ rest between trials. Intraclass correlation coefficients (ICC = 0.916–0.986) and coefficients of variation (CV ≤ 14.5%) were considered acceptable for all variables. Repeated-measures analysis of variance and Freidman’s tests revealed large and significant differences (p ≤ 0.006, η2 = 0.159–0.434, power ≥ 0.859) in ground contact time (GCT), jump height (JH), and subsequently RSI both between trials and repetitions. Pairwise comparisons revealed that repetitions 1–3 produced longer GCTs (p ≤ 0.05, d = 0.41–1.40), lower JHs (p ≤ 0.05, d = 0.31–0.56), and lower RSI values (p ≤ 0.05, d = 0.35–1.24). The shortest GCTs, greatest JHs and greater RSIs occurred between repetitions 7 and 10, with approximately 60% of peak RSIs occurring during these ranges. The sequential estimate technique revealed that seven repetitions were needed to attain stability in mean peak RSI. Non-significant (p = 0.554) and negligible differences (d ≤ 0.09) in the five best RSIs between trials were noted. One trial of the 10/5 RJT is sufficient to evaluate peak RSI in athletes and should reduce data collection time and fatigue.

scholarly journals Agreement between the Open Barbell and Tendo Linear Position Transducers for Monitoring Barbell Velocity during Resistance Exercise

Sports ◽  
2019 ◽  
Vol 7 (5) ◽  
pp. 125
Author(s):  
Adam M. Gonzalez ◽  
Gerald T. Mangine ◽  
Robert W. Spitz ◽  
Jamie J. Ghigiarelli ◽  
Katie M. Sell
Keyword(s):  
Repeated Measures ◽  
Peak Velocity ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Moderate Intensity ◽  
Mean Velocity ◽  
Intraclass Correlation Coefficients ◽  
Coefficients Of Variation ◽  
Repeated Measures Analysis ◽  
Standard Error Of Measurement

To determine the agreement between the Open Barbell (OB) and Tendo weightlifting analyzer (TWA) for measuring barbell velocity, eleven men (19.4 ± 1.0 y) performed one set of 2–3 repetitions at four sub-maximal percentage loads, [i.e., 30, 50, 70, and 90% one-repetition maximum (1RM)] in the back (BS) and front squat (FS) exercises. During each repetition, peak and mean barbell velocity were recorded by OB and TWA devices, and the average of the 2–3 repetitions was used for analyses. Although the repeated measures analysis of variance revealed significantly (p ≤ 0.005) greater peak and mean velocity scores from OB across all intensities, high intraclass correlation coefficients (ICC2,K = 0.790–0.998), low standard error of measurement (SEM2,K = 0.040–0.119 m·s−1), and coefficients of variation (CV = 2–4%) suggested consistency between devices. Positive (r = 0.491–0.949) Pearson correlations between averages and differences (between devices) in peak velocity, as well as associated Bland-Altman plots, showed greater differences occurred as the velocity increased, particularly at low-moderate intensity loads. OB consistently provides greater barbell velocity scores compared to TWA, and the differences between devices were more apparent as the peak velocity increased with low-to-moderate loads. Strength coaches and athletes may find better agreement between devices if the mean velocity scores are only considered.

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