Confidence Interval Estimation for a Difference between Two Dependent Intraclass Correlation Coefficients with Variable Class Sizes

Objective.To measure and compare photoreceptor layer thickness between normal and glaucomatous eyes using spectral-domain optical coherence tomography (OCT).Methods. Thirty-eight healthy normal volunteers and 47 glaucoma patients were included in the analysis. One eye from each participant was randomly selected for macula imaging by a spectral-domain OCT (3D OCT-1000, Topcon, Tokyo, Japan). The foveal and parafoveal (1.5 mm from the fovea) outer nuclear layer (ONL) and inner and outer segments (IS+OS) layer thicknesses were measured by a single masked observer. The measurements were repeated 3 times in a random sample of 30 normal eyes to determine the repeatability coefficient and intraclass correlation coefficient.Results.The measurement variabilities of photoreceptor thickness were low. The respective intraclass correlation coefficients of ONL and IS+OS thicknesses were 0.96 (95% confidence interval: 0.94–0.98) and 0.82 (95% confidence interval 0.70–0.90). While there were no differences in parafoveal ONL and IS+OS thicknesses between normal and glaucoma groups (), the foveal ONL thickness was greater in glaucomatous eyes () than in normal eyes.Conclusions.Glaucomatous damage may involve structural change in the photoreceptor layer.

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Investigating the Dutch Movement-Specific Reinvestment Scale in people with stroke

Clinical Rehabilitation ◽

10.1177/0269215512448381 ◽

2012 ◽

Vol 27 (2) ◽

pp. 160-165 ◽

Cited By ~ 19

Author(s):

Melanie Kleynen ◽

Susy M Braun ◽

Anna JHM Beurskens ◽

Jeanine A Verbunt ◽

Rob A de Bie ◽

...

Keyword(s):

Confidence Interval ◽

Intraclass Correlation ◽

Correlation Coefficients ◽

Limits Of Agreement ◽

Rehabilitation Centre ◽

Altman Plot ◽

Rehabilitation Process ◽

Bland Altman Plot ◽

Intraclass Correlation Coefficients ◽

Conscious Control

Objective: Reinvestment is a phenomenon in which conscious control of movements that are best controlled automatically disrupts performance. The propensity for reinvestment may therefore play an important role in the movement rehabilitation process. The Movement-Specific Reinvestment Scale measures an individual’s propensity for reinvestment. The aim of this study was to translate the scale for use with Dutch participants with stroke and to assess its reliability. Design: A test–retest design. Setting: In community after discharge from rehabilitation centre. Subjects: Forty-five people with stroke. Measures: Reliability of the translated scale was assessed using intraclass correlation coefficients (ICC) and Bland–Altman plot. Results: The ICC was 0.85 (95% confidence interval (CI) 0.74–0.91). Limits of agreement ranged from −2.38 to 3.10. Conclusion: The Dutch Movement-Specific Reinvestment Scale appears to be a reliable tool with which to assess the propensity for movement-specific reinvestment by people with stroke.

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Reliability of Sonoelastography Measurement of Tongue Muscles and Its Application on Obstructive Sleep Apnea

Frontiers in Physiology ◽

10.3389/fphys.2021.654667 ◽

2021 ◽

Vol 12 ◽

Author(s):

Cheng-An Chu ◽

Yunn-Jy Chen ◽

Ke-Vin Chang ◽

Wei-Ting Wu ◽

Levent Özçakar

Keyword(s):

Obstructive Sleep Apnea ◽

Sleep Apnea ◽

Confidence Interval ◽

Odds Ratio ◽

Intraclass Correlation ◽

Correlation Coefficients ◽

Muscle Stiffness ◽

Tongue Muscle ◽

Intraclass Correlation Coefficients ◽

Obstructive Sleep

Few studies have explored the feasibility of shear-wave ultrasound elastography (SWUE) for evaluating the upper airways of patients with obstructive sleep apnea (OSA). This study aimed to establish a reliable SWUE protocol for evaluating tongue muscle elasticity and its feasibility and utility in differentiating patients with OSA. Inter-rater and intra-rater reliability of SWUE measurements were tested using the intraclass correlation coefficients. Submental ultrasound was used to measure tongue thickness and stiffness. Association between the ultrasound measurements and presence of OSA was analyzed using multivariate logistic regression. One-way analysis of variance was used to examine if the values of the ultrasound parameters varied among patients with different severities of OSA. Overall, 37 healthy subjects and 32 patients with OSA were recruited. The intraclass correlation coefficients of intra‐ and inter-rater reliability for SWUE for tongue stiffness ranged from 0.84 to 0.90. After adjusting for age, sex, neck circumference, and body mass index, the risk for OSA was positively associated with tongue thickness [odds ratio 1.16 (95% confidence interval 1.01–1.32)] and negatively associated with coronal imaging of tongue muscle stiffness [odds ratio 0.72 (95% confidence interval 0.54–0.95)]. There were no significant differences in tongue stiffness among OSA patients with varying disease severity. SWUE provided a reliable evaluation of tongue muscle stiffness, which appeared to be softer in patients with OSA. Future longitudinal studies are necessary to investigate the relationship between tongue softening and OSA, as well as response to treatment.

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Reliability of an Active-Knee-Extension Test for Determining Hamstring Muscle Flexibility

Journal of Sport Rehabilitation ◽

10.1123/jsr.1.3.181 ◽

1992 ◽

Vol 1 (3) ◽

pp. 181-187 ◽

Cited By ~ 9

Author(s):

Teddy W. Worrell ◽

Michael K. Sullivan ◽

Joseph J. DeJulia

Keyword(s):

Confidence Interval ◽

Confidence Intervals ◽

Intraclass Correlation ◽

Muscle Length ◽

Correlation Coefficients ◽

Accurate Method ◽

Knee Extension ◽

Hamstring Muscle ◽

Intraclass Correlation Coefficients ◽

Hamstring Flexibility

This study examined the intratester and intertester reliability of an active-knee-extension test (AKET) for determining hamstring muscle length (flexibility). Three testers performed repeated AKET measurements on 22 subjects. Intraclass correlation coefficients (ICC were used to calculate intratester and intertester reliability. Also, standard error of measurements (SEM) were calculated. The ICC and SEM were .96 and 1.82°, respectively, for Tester 1, .99 and 1.75° for Tester 2, and .99 and 1.80° for Tester 3. Intratester 95% confidence intervals ranged from 60.54 to 69.82°. Intertester ICC and SEM for two testers were .93 and 4.81°, respectively. A 95% intertester confidence interval ranged from 56.35 to 75.21 °; this reveals that intertester AKET values contained more error and suggests that only intratester AKET values should be used when comparing hamstring flexibility values. The AKET may provide a more accurate method for determining hamstring flexibility and quantifying changes that occur as a result of injury and stretching procedures.

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Comparison of Three Algorithms Using Thigh-Worn Accelerometers for Classifying Sitting, Standing, and Stepping in Free-Living Office Workers

Journal for the Measurement of Physical Behaviour ◽

10.1123/jmpb.2020-0019 ◽

2021 ◽

Vol 4 (1) ◽

pp. 89-95

Author(s):

Bronwyn Clark ◽

Elisabeth Winker ◽

Matthew Ahmadi ◽

Stewart Trost

Keyword(s):

Confidence Interval ◽

Learning Algorithm ◽

Intraclass Correlation ◽

Correlation Coefficients ◽

Working Hours ◽

Sitting Time ◽

Female Age ◽

Intraclass Correlation Coefficients ◽

The Right

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.

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Map-based assessment of older adults’ life space: validity and reliability

European Review of Aging and Physical Activity ◽

10.1186/s11556-020-00253-7 ◽

2020 ◽

Vol 17 (1) ◽

Author(s):

Timo Hinrichs ◽

Adriana Zanda ◽

Michelle P. Fillekes ◽

Pia Bereuter ◽

Erja Portegijs ◽

...

Keyword(s):

Older Adults ◽

Confidence Interval ◽

Convex Hull ◽

Intraclass Correlation ◽

Correlation Coefficients ◽

Maximum Distance ◽

Validity And Reliability ◽

Life Space ◽

Intraclass Correlation Coefficients ◽

Test Retest Reliability

Abstract Background Map-based tools have recently found their way into health-related research. They can potentially be used to quantify older adults’ life-space. This study aimed to evaluate the validity (vs. GPS) and the test-retest reliability of a map-based life-space assessment (MBA). Methods Life-space of one full week was assessed by GPS and by MBA. MBA was repeated after approximately 3 weeks. Distance-related (mean and maximum distance from home) and area-related (convex hull, standard deviational ellipse) life-space indicators were calculated. Intraclass correlations (MBA vs. GPS and test-retest) were calculated in addition to Bland-Altman analyses (MBA vs. GPS). Results Fifty-eight older adults (mean age 74, standard deviation 5.5 years; 39.7% women) participated in the study. Bland-Altman analyses showed the highest agreement between methods for the maximum distance from home. Intraclass correlation coefficients ranged between 0.19 (95% confidence interval 0 to 0.47) for convex hull and 0.72 (95% confidence interval 0.52 to 0.84) for maximum distance from home. Intraclass correlation coefficients for test-retest reliability ranged between 0.04 (95% confidence interval 0 to 0.30) for convex hull and 0.43 (95% confidence interval 0.19 to 0.62) for mean distance from home. Conclusions While acceptable validity and reliability were found for the distance-related life-space parameters, MBA cannot be recommended for the assessment of area-related life-space parameters.

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