Effects of the kinematic variable, time delay and data length on test-retest reliability of the maximal Lyapunov exponent of human walking.

The maximal Lyapunov exponent (MLE) has been used to quantify the dynamic stability of human locomotion. The method for estimating MLE requires selecting a proper time series of kinematic variables and reconstructing phase space using proper time delay. The data length also affects the reliability of the measured MLE. However, there has been no criterion for the choice of the time series, time delay or data length. Here, we quantified the effect of these factors on the test-retest reliability of MLE estimations. We recruited 15 young and healthy adults and let them walk on a treadmill three times. We calculated MLE employing various lengths of time series of 18 frequently used kinematic variables and two typical choices of time delay: fixed delay and delay selected by average mutual information algorithm. Then, we measured the intraclass correlation coefficient (ICC) of the measured MLE under each condition. Our results show that the choice of time delay does not affect reliability. Five among the 18 kinematic variables enabled excellent reliability with ICC above 0.9 within 450 strides and also enabled ICC above 0.75 even with 60 or less strides. These findings can contribute to establishing the criteria for measuring the dynamic stability of human walking.

Personality testing of large language models: limited temporal stability, but highlighted prosociality.

As large language models (LLMs) continue to gain popularity due to their human-like traits and the intimacy they offer to users, their societal impact inevitably expands. This leads to the rising necessity for comprehensive studies to fully understand LLMs and reveal their potential opportunities, drawbacks and overall societal impact. With that in mind, this research conducted an extensive investigation into seven LLMs, aiming to assess the temporal stability and inter-rater agreement on their responses on personality instruments in two time points. In addition, LLMs' personality profile was analysed and compared with human normative data. The findings revealed varying levels of inter-rater agreement in the LLMs' responses over a short time, with some LLMs showing higher agreement (e.g. Llama3 and GPT-4o) compared with others (e.g. GPT-4 and Gemini). Furthermore, agreement depended on used instruments as well as on domain or trait. This implies the variable robustness in LLMs' ability to reliably simulate stable personality characteristics. In the case of scales which showed at least fair agreement, LLMs displayed mostly a socially desirable profile in both agentic and communal domains, as well as a prosocial personality profile reflected in higher agreeableness and conscientiousness and lower Machiavellianism. Exhibiting temporal stability and coherent responses on personality traits is crucial for AI systems due to their societal impact and AI safety concerns.

[Reference ranges and test-retest reliability of subject visual horizontal from different head-tilt angles in young healthy adults].

Objective:To establish the normal values of subjective visual horizontal（SVH） under different head tilt angles, analyze the test-retest reliability, and provide a normal value reference for the refined diagnosis and functional assessment of SVH in clinical vestibular disorders. Methods:Thirty-one healthy young people were selected to wear visual reality glasses to test SVH data in five different head tilt angles: upright head position 0°, head tilted 45°to the left（L45°ï¼‰, head tilted 45° to the right（R45°ï¼‰, head tilted 90° to the left（L90°ï¼‰, and head tilted 90° to the right（R90°ï¼‰, and were re-tested 2 weeks later. Results:①The normal values of SVH at 0°, L45°, R45°, L90°, and R90°were 0.30±1.32, 5.94±5.54, -11.44±5.32, -0.87±8.63, -2.70±8.02, respectively. ②The 95% confidence intervals of SVH at 0°, L45°, R45°, L90°, and R90° were: （-2.34,2.94）,（-5.14,17.02）,（-22.08,-0.80）,（-18.13,16.39）,（-18.74，13.34）, respectively. The ratio of asymmetry in the absolute value of bilateral 45° deviation was 26.4% and the ratio of asymmetry in the absolute value of bilateral 90° deviation was 1.3%. ③The intra-class correlation coefficient（ICC） for 0°, L45°, R45°, L90° and R90° was 0.625, 0.641, 0.564, 0.769, 0.656, respectively. Conclusion:SVH has good test-retest reliability and high clinical test stability and stability. The data on normal values of SVH at different head tilt angles established in this study can provide clinical references for the refined diagnosis and functional assessment of vestibular system disorders.

Computational phenotyping of aberrant belief updating in individuals with schizotypal traits and schizophrenia.

BACKGROUND: Psychotic experiences are thought to emerge from various interrelated patterns of disrupted belief updating, such as overestimating the reliability of sensory information and misjudging task volatility. Yet, these substrates have never been jointly addressed under one computational framework and it is not clear to what degree they reflect trait-like computational patterns. METHODS: We introduced a novel hierarchical Bayesian model that describes how individuals simultaneously update their beliefs about the task volatility and noise in observation. We applied this model to data from a modified Predictive inference task in a test-retest study with healthy volunteers (N=45, 4 sessions) and examined the relationship between model parameters and schizotypal traits in a larger online sample (N = 437) and in a cohort of patients with schizophrenia (N = 100). RESULTS: The interclass correlations were moderate to high for model parameters and excellent for averaged belief trajectories and precision-weighted learning rates estimated through hierarchical Bayesian inference. We found that uncertainty about the task volatility was related to schizotypal traits and to positive symptoms in patients, when learning to gain rewards. In contrast, negative symptoms in patients were associated with more rigid beliefs about observational noise, when learning to avoid losses. CONCLUSION: These findings suggest that individuals with schizotypal traits across the psychosis continuum are less likely to learn or utilize higher-order statistical regularities of the environment and showcase the potential of clinically relevant computational phenotypes for differentiating symptom groups in a transdiagnostic manner.

Gait and Balance Assessments with Augmented Reality Glasses in People with Parkinson's Disease: Concurrent Validity and Test-Retest Reliability.

State-of-the-art augmented reality (AR) glasses record their 3D pose in space, enabling measurements and analyses of clinical gait and balance tests. This study's objective was to evaluate concurrent validity and test-retest reliability for common clinical gait and balance tests in people with Parkinson's disease: Five Times Sit To Stand (FTSTS) and Timed Up and Go (TUG) tests. Position and orientation data were collected in 22 participants with Parkinson's disease using HoloLens 2 and Magic Leap 2 AR glasses, from which test completion durations and durations of distinct sub-parts (e.g., sit to stand, turning) were derived and compared to reference systems and over test repetitions. Regarding concurrent validity, for both tests, an excellent between-systems agreement was found for position and orientation time series (ICC(C,1) > 0.933) and test completion durations (ICC(A,1) > 0.984). Between-systems agreement for FTSTS (sub-)durations were all excellent (ICC(A,1) > 0.921). TUG turning sub-durations were excellent (turn 1, ICC(A,1) = 0.913) and moderate (turn 2, ICC(A,1) = 0.589). Regarding test-retest reliability, the within-system test-retest variation in test completion times and sub-durations was always much greater than the between-systems variation, implying that (sub-)durations may be derived interchangeably from AR and reference system data. In conclusion, AR data are of sufficient quality to evaluate gait and balance aspects in people with Parkinson's disease, with valid quantification of test completion durations and sub-durations of distinct FTSTS and TUG sub-parts.

Factor analysis and evaluation of one-year test-retest reliability of the 33-item Childhood Trauma Questionnaire in Chinese adolescents.

The 33-item Childhood Trauma Questionnaire (CTQ-33) is a recently developed tool expanded from the 28-item Childhood Trauma Questionnaire (CTQ-28) to assess childhood trauma events, which showed good test-retest reliability over 2 weeks. However, little is known regarding the factor structure and long-term test-retest reliability of the CTQ-33. To fill such a gap, this study investigated the factorial validity of the CTQ-33 and test-retest reliability of the scale over a relatively long interval of 1 year. Data on demographics, the CTQ-33 scores, and mental health statuses such as depressive/anxiety symptoms were collected in Chinese adolescents (n = 188) twice across a one-year period. Results of the confirmatory factor analysis (CFA) revealed that the Chinese version of CTQ-33 has close factor validity when compared to the original CTQ-28 in college students. Furthermore, the total and most subscale scores of the CTQ-33 have fair to good test-retest reliability (intra-class correlation coefficients >0.6 for the total score, and > 0.4 for most subscales), except for the physical abuse subscale. Moreover, we replicated previous findings of significant positive relationships between levels of different childhood trauma subtypes using the CTQ-33. These findings provide initial evidence supporting that the CTQ-33 is overall reliable to assess childhood traumatic events in adolescents over relatively long intervals.

Test-retest reproducibility of absolute myocardial blood flow obtained using stress dynamic CT myocardial perfusion imaging.

Background: Coronary artery disease (CAD) and coronary microvascular disease (CMD) are significant contributors to angina pectoris, necessitating reliable diagnostic techniques for effective management. While positron emission tomography has been the non-invasive gold standard for myocardial blood flow (MBF) quantification, stress dynamic CT myocardial perfusion imaging (CTMPI) has emerged as a promising alternative. This study aimed to evaluate the test-retest reproducibility of MBF measurements obtained using dynamic CTMPI. Methods: The study retrospectively analyzed MBF values from two dynamic CTMPI examinations conducted in the same patient cohort (n = 30) to examine the consistency of MBF quantification and the ability to visually detect and grade abnormal perfusion suggesting ischemia between the tests. Global and remote MBF were defined as the mean MBF and the maximum MBF of all segments, respectively. Results: MBF quantification revealed strong linear correlations between the tests (r = 0.89 for global MBF, r = 0.88 for remote MBF, and r = 0.82 for all segments), and intraclass correlation coefficients reflected high agreement between the tests (0.94 for global MBF, 0.93 for remote MBF, and 0.90 for all segments). Bland-Altman plots indicated a negligible mean difference with acceptable limits of agreements between the tests for global MBF, remote MBF, and all segments. Visual assessment of the CTMPI maps for abnormal perfusion suggesting ischemia yielded a good inter-test agreement with a weighted kappa value of 0.80. Conclusion: Dynamic CTMPI can consistently reproduce absolute MBF values and reliably detect myocardial perfusion abnormalities, potentially making it a robust diagnostic tool for evaluating the presence and severity of CAD and CMD.

The Parenting and Family Adjustment Scales (PAFAS) questionnaire: psychometric qualities of the parenting scale in two large Brazilian birth cohorts.

Objective: Analyse the psychometric properties of the Portuguese version of the PAFAS (Parenting and Family Adjustment Scales) parenting scale, using data from two large Brazilian birth cohorts. Methods: The original PAFAS parenting scale, which consists of 18 items (parental inconsistency 5 items, coercive parenting 5 items, positive encouragement 3 items, and parent-child relationship 5 items) was applied in two Brazilian birth cohorts in Pelotas (ages 4 [n = 4010] and 6-7 [n = 3867]) and Rio Grande (age 3 [n = 992]). Confirmatory factor analysis was conducted, and internal consistency assessed, as well as construct validity in relation to maternal depression measured on the Edinburgh Postnatal Depression Scale. Results: The model with a structure of 4 subscales showed that the global scale of parenting on the PAFAS had a good fit, but certain items did not fit well on sub-scales and were removed (2 items from parental inconsistency, 1 from coercive parenting, and 1 from positive encouragement). The original form of the parent-child relationship sub-scale was maintained. Considering the total PAFAS parenting score, we found that mothers with maternal depression had a higher likelihood of more problematic parental practices than mothers without depression. Conclusions: A revised 14-item PAFAS parenting scale has good psychometric properties and we encourage its use in Brazilian populations.

Test-retest and inter-rater reliability of two devices measuring tactile mechanical detection thresholds in healthy adults: Semmes-Weinstein monofilaments and the cutaneous mechanical stimulator.

INTRODUCTION/AIMS: Limitations exist in evaluating mechanical detection thresholds (MDTs) due to a lack of dependable electronic instruments designed to assess Aß fibers and measure MDTs across different body areas. This study aims to evaluate the test-retest and inter-rater reliability of the cutaneous mechanical stimulator (CMS), an electronic tactile stimulator, in quantifying MDTs. METHODS: Using a test-retest design, participants underwent assessments of MDTs using Semmes-Weinstein monofilaments (SWM) and the CMS. This study included 27 healthy volunteers (mean age 24.07 ± 3.76 years). Two raters assessed MDTs using SWM and the CMS at two stimulation sites (the left hand and foot) in two experimental sessions approximately 2 weeks apart. RESULTS: MDTs using SWM and the CMS showed excellent reliability on the hand (intraclass correlation coefficient [ICC] = .84) and foot (ICC = .90). A comparison of results obtained at the two sessions showed that MDTs on the hand displayed good reliability for both SWM (ICC = .63) and the CMS (ICC = .73), whereas MDTs on the foot displayed fair reliability for SWM (ICC = .50) and the CMS (ICC = .42). MDTs exhibited good inter-rater reliability with SWM (ICC = .66) and excellent inter-rater reliability with the CMS (ICC = .82) on the hand, as well as showing fair inter-rater reliability with SWM (ICC = .53) and good inter-rater reliability with the CMS (ICC = .60) on the foot. DISCUSSION: The CMS showed superior inter-rater reliability, indicating its potential as a valuable tool for assessing tactile sensitivity in research and clinical settings.

The Reliability of Field-Based Static and Dynamic Balance Tests in Primary School-Aged Autistic Children.

Previous research has proven that the balance of autistic children is poor. However, the reliability of assessing balance in this cohort has been inadequately researched. This study therefore aimed to examine if field-based static and dynamic balance tests can be reliably assessed in autistic children, to determine the number of familiarisation sessions required and whether autistic severity impacts on the reliability of these balance tests. The balance of eighteen primary school-aged autistic children was assessed three times a week over five weeks, using the flamingo balance test, a modified version of the balance error scoring system (BESS), the low beam walking test, and the heel to toe walking test. Reliability criteria included an intraclass correlation coefficient (ICC) level of ≥0.75 and a coefficient of variance (CV%) of ≤46% for the low beam walking test, the heel to toe walking test, and the BESS, and a CV% of ≤82% or the flamingo balance test. Inter-session reliability was achieved and required the least number of familiarisation sessions for the flamingo balance test, compared to the low beam walking test, which required a greater number of familiarisation sessions to achieve inter-session reliability. The heel to toe walking test and the BESS achieved inter-session reliability and familiarisation in an acceptable time frame. Due to the large CV% values reported in the current study, practitioners need to be aware that balance interventions need to achieve improvements greater than the CV% in this cohort.

Test-retest reliability and minimal detectable change in pelvis and lower limb coordination during running assessed with modified vector coding.

The objective of this study was to evaluate the reliability of Modified Vector Coding in assessing the coordination and coordination variability of the lower limbs and pelvis during running and to determine the Minimal Detectable Change (MDC). Twenty-five healthy runners participated in a biomechanical analysis of treadmill running using a motion capture system. Modified vector coding was applied to assess the three-dimensional coordination among various pelvis and lower limb segmental couplings. Reliability was assessed using the Intraclass Correlation Coefficient (ICC), Standard Error of Measurement (SEM), MDC, and Bland-Altman analysis to ascertain measurement consistency, agreement, and the smallest clinically meaningful change that exceeds measurement error. The test-retest reliability for 33 of 42 segmental couplings analyzed was good to excellent, with ICC values ranging from 0.613 to 0.928 (p <0.05), which substantiates the robustness of modified vector coding in running biomechanics. However, nine couplings, particularly femur-tibia in the sagittal plane during midstance and foot in the frontal plane-tibia in the transverse plane during late stance, exhibited poor to moderate reliability. These findings underscore the need for cautious interpretation due to significant proportional bias (p <0.05). SEM and MDC provided insights into the precision and minimal clinically significant changes for each coupling. The findings confirm the reliability of modified vector coding for biomechanical analysis in running, with most couplings demonstrating consistent high reliability. Nevertheless, specific couplings should be interpreted with caution due to potential measurement errors. The application of MDC highlights the precision of modified vector coding in biomechanical analyses and emphasizes the importance of careful interpretation to improve clinical and research outcomes in running-related injuries.

An Assessment of the Ratio between Upper Body Push and Pull Strength in Female and Male Elite Swedish Track and Field Throwers.

Data on the strength ratio between agonist and antagonist muscles are frequently examined in sports testing, given its correlation with athletic performance. The purpose of this study was to determine the agonist-to-antagonist ratio of upper body strength in female and male elite Swedish track and field throwers using a new push (bench press) and pull (supine bench row) test device, and to determine its reliability. The study involved eight female and nine male athletes, aged 19-29 years, engaging, respectively, in discus, hammer, and shot put competitions at both national and international levels. The athletes' maximum isometric force was assessed during the bench press (push) and supine bench row (pull) exercises, respectively, using a custom-built test device. The test-retest reliability of the device was also examined. The total push-to-pull strength ratio for the female throwers was 1.15, whereas male throwers demonstrated a ratio of 1.22. Total push and pull force for the female throwers was significantly less than for the male throwers (5511 N vs. 8970 N, p < 0.001). Intraclass correlation coefficients ranged from 0.93 to 0.96 for the bench press and supine bench row exercise, indicating that the push and pull test device was highly reliable. The main findings of this study were that elite female and male discus, hammer, and shot put throwers exhibited 15% and 22% more pushing (bench press) than pulling (supine bench row) strength. Push and pull strength in the female throwers ranged from 47% to 71% of that of the male throwers. The push and pull test device is a reliable tool in establishing the agonist-to-antagonist ratio of upper body strength of athletes. Coaches and athletes may benefit from examining upper body push and pull strength ratios for training planning and prescription.

Reliability and validity of sprint performance using the Alex7 motorized device.

Introduction: Advancements in technology have recently made it possible to implement effective training solutions across different environmental conditions. This study evaluated the reliability and validity of measures obtained from the innovative motorized device, Alex7 (Inosportas, Lithuania), and differences in speed and kinematic characteristics between resisted and assisted sprinting in young football players. Methods: Twenty-seven male athletes (mean age: 16.5 ± 0.8 years; height: 179.5 ± 6.9 cm; body weight: 67.7 ± 8.3 kg) each performed 30-m sprints twice under three different conditions: regular, resisted, and assisted sprinting. The Alex7 device provided the assistance and resistance during sprints. Results were compared with those from Witty timing gates. Ground contact time, flight time, stride length, and pace were measured using the OptoJump system. Reliability was assessed using two-way mixed intraclass correlation coefficients (ICCs) for single measures, the standard error of the mean (SEM), and the coefficient of variation (CV). Pearson's correlation coefficient determined the associations between Alex7 and Witty timing systems. Criterion-referenced validity was based on the mean difference and CV. Systematic bias was determined by limits of agreement using Bland-Altman analysis. Results: Running times obtained using the Alex7 equipment exhibited good to excellent test-retest reliability between sessions (ICC, 0.83-0.94) and good to excellent correlation (Pearson's r = 0.88-0.98) between the Alex7 and Witty systems in both assisted and resisted running conditions. However, the Alex7 device consistently produced longer running times than the Witty device (up to 0.16 s difference, p < 0.001). The different running conditions produced substantial variations in kinematic variables, such as stride length, ground contact time, and running speed (p < 0.001 for all), but the effects on flight time and running pace were smaller. Discussion: The Alex7 device shows high reliability for creating resisted and assisted running conditions for young football players. However, it tends to overestimate running time, necessitating caution when assessing the time parameters.

Repeatability and minimal detectable change including clothing effects for smartphone-based 3D markerless motion capture.

OpenCap, a smartphone- and web-based markerless system, has shown acceptable accuracy compared to marker-based systems, but lacks information on repeatability. This study fills this gap by evaluating the intersession repeatability of OpenCap and investigating the effects of clothing on gait kinematics. Twenty healthy volunteers participated in a test-retest study, performing walking and sit-to-stand tasks with minimal clothing and regular street wear. Segment lengths and lower-limb kinematics were compared between both sessions and for both clothing conditions using the root-mean-square-deviation (RMSD) for entire waveforms and the standard error of measurement (SEM) and minimal detectable change (MDC) for discrete kinematic parameters. In general, the RMSD test-retest values were 2.8 degrees (SD: 1.0) for walking and 3.3 degrees (SD: 1.2) for sit-to-stand. The highest intersession variability was observed in the trunk, pelvis, and hip kinematics of the sagittal plane. SEM and MDC values were on average 2.2 and 6.0 degrees, respectively, for walking, and 2.4 and 6.5 degrees for sit-to-stand. Clothing had minimal effects on kinematics by adding on average less than one degree to the RMSD values for most variables. The segment lengths showed moderate to excellent agreement between both sessions and poor to moderate agreement between clothing conditions. The study highlights the reliability of OpenCap for markerless motion capture, emphasizing its potential for large-scale field studies. However, some variables showed high MDC values above 5 degrees and thus warrant further enhancement of the technology. Although clothing had minimal effects, it is still recommended to maintain consistent clothing to minimize overall variability.

Which Gait Tasks Produce Reliable Outcome Measures of Freezing of Gait in Parkinson's Disease?

Background: Measurement of freezing of gait (FOG) relies on the sensitivity and reliability of tasks to provoke FOG. It is currently unclear which tasks provide the best outcomes and how medication state plays into this. Objective: To establish the sensitivity and test-retest reliability of various FOG-provoking tasks for presence and severity of FOG, with (ON) and without (OFF) dopaminergic medication. Methods: FOG-presence and percentage time frozen (% TF) were derived from video annotations of a home-based FOG-provoking protocol performed in OFF and ON. This included: the four meter walk (4MW), Timed Up and Go (TUG) single (ST) and dual task (DT), 360° turns in ST and DT, a doorway condition, and a personalized condition. Sensitivity was tested at baseline in 63 definite freezers. Test-retest reliability was evaluated over 5 weeks in 26 freezers. Results: Sensitivity and test-retest reliability were highest for 360° turns and higher in OFF than ON. Test-retest intra-class correlation coefficients of % TF varied between 0.63-0.90 in OFF and 0.18-0.87 in ON, and minimal detectable changes (MDCs) were high. The optimal protocol included TUG ST, 360° turns ST, 360° turns DT and a doorway condition, provoking FOG in all freezers in OFF and 91.9% in ON and this could be done reliably in 95.8% (OFF) and 84.0% (ON) of the sample. Combining OFF and ON further improved outcomes. Conclusions: The highest sensitivity and reliability was achieved with a multi-trigger protocol performed in OFF + ON. However, the high MDCs for % TF underscore the need for further optimization of FOG measurement.

Freezing of gait is a very burdensome and episodic symptom in Parkinson's disease that is difficult to measure. Measurement of freezing is needed to determine whether someone has freezing and how severe this is, and relies on observation during a freezing-triggering protocol. However, it is unclear what protocol is sufficiently sensitive to trigger freezing in many freezers, and whether freezing can be triggered reliably at different timepoints. Here, we investigated 1) which tasks can trigger freezing-presence and freezing-severity sensitively and reliably, 2) how medication state influences this, and 3) what task combination was most reliable. Sixty-three patients with daily freezing performed several freezing-triggering tasks in their homes, both with (ON) and without (OFF) anti-Parkinsonian medication. In twenty-six patients, the measurement was repeated 5 weeks later to determine test-retest reliability. First, we found that performing 360° turns in place with a cognitive dual task was the most sensitive and reliable task to trigger FOG. Second, sensitivity and reliability were better in OFF than in ON. Third, the most reliable protocol included: the Timed-Up and Go, 360° turns in place with and without the dual task, and a doorway condition. This protocol triggered freezing in all patients in OFF and 91.9% in ON and did so reliably in 95.8% (OFF) and 84.0% (ON) of the sample. We recommend to measure freezing with this protocol in OFF + ON, which further improved reliability. However, the measurement error for freezing-severity was high, even for this optimal protocol, underscoring the need for further optimization of freezing measurement.

Amygdala fMRI-A Critical Appraisal of the Extant Literature.

Even before the advent of fMRI, the amygdala occupied a central space in the affective neurosciences. Yet this amygdala-centred view on emotion processing gained even wider acceptance after the inception of fMRI in the early 1990s, a landmark that triggered a goldrush of fMRI studies targeting the amygdala in vivo. Initially, this amygdala fMRI research was mostly confined to task-activation studies measuring the magnitude of the amygdala's response to emotional stimuli. Later, interest began to shift more towards the study of the amygdala's resting-state functional connectivity and task-based psychophysiological interactions. Later still, the test-retest reliability of amygdala fMRI came under closer scrutiny, while at the same time, amygdala-based real-time fMRI neurofeedback gained widespread popularity. Each of these major subdomains of amygdala fMRI research has left its marks on the field of affective neuroscience at large. The purpose of this review is to provide a critical assessment of this literature. By integrating the insights garnered by these research branches, we aim to answer the question: What part (if any) can amygdala fMRI still play within the current landscape of affective neuroscience? Our findings show that serious questions can be raised with regard to both the reliability and validity of amygdala fMRI. These conclusions force us to cast doubt on the continued viability of amygdala fMRI as a core pilar of the affective neurosciences.

Confidence sets for intraclass correlation coefficients in test-retest curve measurements.

Evaluating test-retest reliability is crucial in biomechanical research, as it validates experimental results. While methods for reliability of scalar outcome variables are well-established, methods to assess reliability of continuous curve data (such as joint angle trajectories during gait) remain less explored. This study investigates methods for constructing confidence sets for curve-level intraclass correlation coefficients (ICC), which can be expressed as either an ICC curve or an integrated ICC. Currently, no standardised guidelines exist in biomechanics for reporting curve-level ICC uncertainty. Nonparametric bootstrapping techniques are proposed for both the ICC curve's confidence bands and the integrated ICC's confidence intervals, and these methods are validated through Monte Carlo simulations, covering various effect sizes and curve characteristics. Additionally, these methods are applied to assess the test-retest reliability of knee kinematics in three different planes during landing of one-leg hops, where less uncertainty is observed for the ICC curve and integrated ICC in the frontal plane compared to other planes. When the entire time domain is of primary empirical interest, we recommend using a rank-based bootstrap confidence band to express ICC uncertainty, as it yields increasingly precise and valid results as the number of individuals increases, with the coverage rate approaching the correct level of 95%. When a single summary metric is of primary interest, we recommend using the integrated ICC along with a typical bootstrap confidence interval based on the normal distribution, as the coverage rate remains adequately accurate and stable at around the correct level of 95% across varying number of individuals.

Reliability and minimal detectable change of the Yoni task for the theory of mind assessment.

Introduction: The Theory of Mind (ToM) assessment is becoming essential to evaluate the response to a social cognition intervention and to monitor the progression of social abilities impairment in atypical conditions. In the Italian setting, the Yoni task has been recently validated in its short version (the Yoni-48 task) to evaluate ToM in the clinical setting. The present study aimed to verify the test-retest reliability and the Minimal Detectable Change (MDC) of the Yoni-48 task. Methods: The Yoni-48 task was administered to 229 healthy adults at two evaluation sessions 3 weeks apart (mean days between sessions = 20.35 ± 1.75) by a psychologist. The test-retest reliability of the Yoni-48 task accuracy and response time was tested by the Intraclass Correlation Coefficient (ICC2,1, two-way random model, absolute agreement type). Then, the MDC95 and MDC90 were computed based on the standard error of measurement. Finally, the 95% limits of agreement were plotted (LOA plot) to visualize the difference and mean score of each pair of measurements. Results: The total Yoni-48 task accuracy, but not the response time score, showed a high ICC (>0.80), with an MDC of 0.10. By plotting the LOA plot for the accuracy score no systematic trends were observed. Discussion: This evidence will support the adoption of the Yoni task in longitudinal designs.

Reliability of dynamic and isometric upper muscle strength testing in breast cancer survivors.

Breast cancer is the most common cancer in women worldwide, and its treatment usually involves a combination of many medical procedures, including surgery, chemotherapy, radiotherapy, and hormonal therapy. One of the detrimental effects on physical function is reduced upper limb muscle strength. This study aimed to evaluate upper body strength intra-day and inter-day (test-retest) reliability using the handgrip strength test (HGS) and the bilateral isometric bench press (BIBP) and the test-retest reliability of the one repetition maximum on the bench press (BP-1RM) in breast cancer survivors (BCS). Thirty-two (52.94 ± 8.99 yrs) BCS participated in this study. The muscle strength tests were performed in two different moments, three to seven days apart. Intraclass coefficient correlation (ICC) and coefficient of variation (CV) were used to assess the reliability. Standard error of measurement (SEM), typical error of measurement (TEM), and minimally detectable change (MDC) analyses were performed. The Bland-Altman analysis was used to assess the agreement between test-retest. We found a reliability that can be described as "high" to "very high" (ICC ≥ 0.88; CV ≤ 10%) for intra-day and test-retest. SEM% and MDC% were lower than 5% and 11%, respectively, for all intra-day testing. SEM% and TEM% ranged from 3% to 11%, and MDC% ranged from 9% to 23% in the test-retest reliability. The agreement demonstrated a systematic bias ranging from 2.3% to 6.0% for all testing, and a lower systematic bias may be presented in the non-treated side assessed by HGS and BIBP. HGS, BIBP, and BP-1RM assessments are reliable for measuring upper-body muscle strength in BCS.

Test-retest reliability, practice effects and estimates of change: A study on the Mindmore digital cognitive assessment tool.

The present study aimed to establish test-retest reliability and investigate practice effects of the Mindmore cognitive assessment tool, a digital adaptation of traditional pencil and paper tests designed for self-administration. Additionally, normative change scores for the most frequently used tests were derived. A total of 149 healthy Swedish adults (aged 20-79) completed the test battery twice, 1 month apart. The battery assessed attention and processing speed, memory, language, visuospatial functions, and executive functions. Test-retest reliability, measured by ICC and Spearman coefficients, and practice effects were estimated for 22 main-scores and 33 sub-scores. Regression models were used to assess change in performance while controlling for demographics, computer equipment, testing location (online or in-laboratory) and baseline performance for 12 main-scores and nine sub-scores. Test-retest reliability was good for 11 main-scores (≥0.70), satisfactory for five (0.60-0.69), and minimal for six (<0.60) albeit three having satisfactory sub-scores. Practice effects were observed for tests with a major speed component, but not for reaction time, sustained attention, verbal memory and naming (alternate forms), nor visuospatial functions. Trackpad negatively influenced change for one test. Demographics and testing location did not significantly affect the change scores. Our study provides support for test-retest reliability and practice effects of the Mindmore cognitive assessment tool which were comparable to those of traditional tests. These findings, together with the normative change scores, can aid researchers and clinicians in interpreting test results and distinguishing between normal variations in performance and changes indicative of clinical impairment.