Test Occasions Research Articles

Adaptive Measurement of Change in the Context of Item Parameter Drift

Adaptive measurement of change (AMC) uses computerized adaptive testing (CAT) to measure and test the significance of intraindividual change on one or more latent traits. The extant AMC research has so far assumed that item parameter values are constant across testing occasions. Yet item parameters might change over time, a phenomenon termed item parameter drift (IPD). The current study examined AMC’s performance in the context of IPD with unidimensional, dichotomous CATs across two testing occasions. A Monte Carlo simulation revealed that AMC false and true positive rates were primarily affected by changes in the difficulty parameter. False positive rates were related to the location of the drift items relative to the latent trait continuum, as the administration of more drift items spuriously increased the magnitude of estimated trait change. Moreover, true positive rates depended upon an interaction between the direction of difficulty parameter drift and the latent trait change trajectory. A follow-up simulation further showed that the number of items in the CAT with parameter drift impacted AMC false and true positive rates, with these relationships moderated by IPD characteristics and the latent trait change trajectory. It is recommended that test administrators confirm the absence of IPD prior to using AMC for measuring intraindividual change with educational and psychological tests.

Reliability and Validity of Four Step Tests in Older Adults With Dementia.

To determine the test-retest and inter-rater reliability, concurrent and discriminative validity of the Four Square Step Test (FSST), the Choice Stepping Reaction Time Test (CSRTT), the Maximum Step Length Test (MSLT), and the Alternate Step Test (AST) in older adults with dementia. Thirty-seven older adults with dementia who could walk independently for at least 10m were recruited at community centers and day care centers for older adults. The participants completed the step tests conducted by two independent raters on three separate testing occasions within 3weeks. In addition, the physical and cognitive function of the participants were evaluated at baseline. The FSST, CSRTT, and MSLT showed good-to-excellent test-retest reliability (intraclass correlation coefficient [ICC]=0.83-0.91), and the AST exhibited fair test-retest reliability (ICC=0.70). All the step tests showed good-to-excellent inter-rater reliability (ICC=0.75-0.94). The step tests had moderate-to-strong correlations with various physical and cognitive measures (Pearson correlation coefficients=0.34-0.72). The MSLT side step and AST could differentiate between individuals who did and did not use a walking stick to ambulate (p≤0.046). The FSST, CSRTT, and AST could differentiate between individuals with and without a major neurocognitive impairment (p≤0.005). The FSST, CSRTT, and MSLT were reliable and valid for examining the stepping performance of older adults with dementia. Clinicians can use these tests to evaluate the physical and cognitive function of this population and identify those with significant cognitive impairment. Clinical Trial Registration number: NCT04296123.

Global Lung Function Initiative reference values for multiple breath washout indices.

Multiple breath washout is a lung function test based on tidal breathing that assesses lung volume and ventilation distribution. The aim of this analysis was to use the Global Lung Function Initiative methodology to develop all-age reference equations for the multiple breath washout indices lung clearance index (LCI) and functional residual capacity (FRC). Multiple breath washout data from healthy individuals were collated from sites. Data were re-analysed using the latest software versions. Reference equations were derived using the lambda-mu-sigma method using the generalised additive models of location shape and scale programme in R. The impact of equipment type, inert tracer gas and equipment dead space volume on the derived reference ranges were investigated. Data from 23 sites (n=3647 test occasions) were submitted. Reference equations were derived from 1579 unique observations from participants between the ages of 2 and 81 years. Equipment type, inert tracer gas and equipment dead space volume did not significantly affect the prediction equations for either LCI or FRC. Reference equations for LCI include age as the only predictor, whereas sex-specific reference equations for FRC included height and age. Global Lung Function Initiative reference equations for multiple breath washout variables provide a standard for reporting and interpretation of LCI and FRC.

Development and a validation study of comprehensive prescription writing rubrics for medical students

Background: Prescribing is a complex task for physicians, with many global reports of errors. This study evaluates a comprehensive rubric for medical student prescribing skills regarding validity and reliability. Methods: Twenty-one third-year medical students participated in three separate prescribing exams. Two pharmacology professors rated the students' prescriptions using a rubric covering ten criteria. Messick validity framework was utilised to enhance the study’s validity. Generalisability theory (G-theory) helped determine the source of variance and the optimal number of raters and test occasions. Results: Content validity was ensured by three experts and alignment with the Thai Medical Council criterion. The Inter-rater and test-retest reliability were acceptable. The rubric had a Cronbach's alpha 0.70 with item-test correlation, all above 0.40. G-theory indicated that 54.93% of the total variance was due to performance and 27.57% to the interaction between performance and occasions, with a minimal residual variance of 4.28%. To reach an acceptable Phi-coefficient (≥0.70), three occasions with one rater (Phi-coefficient=0.76) or two occasions with two raters (Phi-coefficient=0.72) are needed. Conversely, the Phi-coefficient was low on a single occasion. Conclusion: The study introduces a comprehensive rubric and description of a prescription writing programme to minimise potential prescribing errors in pre-clinical years. Furthermore, more assessment opportunities enhance knowledge retention and assessment reliability.

Translation and psychometric evaluation of composite feedback-seeking behavior questionnaire among Iranian medical residents

BackgroundProactively seeking feedback from clinical supervisors, peers or other healthcare professionals is a valuable mechanism for residents to obtain useful information about and improve their performance in clinical settings. Given the scant studies investigating the limited aspects of psychometrics properties of the feedback-seeking instruments in medical education, this study aimed to translate the feedback-seeking behavior scales (frequency of feedback-seeking, motives of feedback-seeking, and promotion of feedback-seeking by supervisors) into Persian and evaluate the psychometric properties of the composite questionnaire among medical residents at Tehran University of Medical Sciences in Iran.MethodsIn this cross-sectional study, feedback-seeking behavior scales were translated through the forward–backward method, and its face validity and content validity were assessed by 10 medical residents and 18 experts. The test-retest reliability was evaluated by administering the questionnaire to 20 medical residents on two testing occasions. A convenience sample of 548 residents completed the questionnaire. Construct validity was examined by exploratory factor analysis and confirmatory factor analysis and concurrent validity was determined by Pearson’s correlation coefficient.ResultsContent validity assessment showed that the CVR (0.66 to 0.99) and CVI (0.82 to 0.99) values for items and S-CVI values (0.88 to 0.99) for scales were satisfactory. The exploratory and confirmatory factor analysis demonstrated that the models were confirmed with eight items and two factors (explaining 70.98% of the total variance) for the frequency of feedback-seeking scale, with 16 items and four factors (explaining 73.22% of the total variance) for the motives of feedback seeking scale and with four items and one factor (explaining 69.46% of the total variance) for promotion of feedback-seeking by supervisors. AVE values greater than 0.5 and discriminant validity correlations significantly less than 1.0 demonstrated that the total scores of the composite feedback-seeking behavior questionnaire had a favorable fit and the questions could fit their respective factors, and the latent variables were distinct. We found positive and significant correlations between the three scales and their subscales.ConclusionThe results of the present study supported the validity and reliability of the Persian composite feedback-seeking behavior questionnaire for assessing feedback-seeking behaviors in medical residents. Applying the questionnaire in residency programs may enhance the quality of clinical education.

Psychometric Evaluation of the Bahasa Malaysia Version of the Lymphedema Functioning, Disability, and Health Questionnaire for Upper Limb Lymphedema in Patients with Breast Cancer-Related Lymphedema.

Background: Breast cancer-related lymphedema (BCRL) is the most prevalent comorbidity that occurs following breast cancer treatments and has negative impact on the patients' quality of life (QoL). The Lymphedema Functioning, Disability, and Health Questionnaire for Upper Limb Lymphedema (Lymph-ICF-UL) is a valid and reliable instrument in assessing the QoL of patients with BCRL. However, the Bahasa Malaysia (BM) version is not available yet. This study aimed to translate the Lymph-ICF-UL into BM and to evaluate its validity and reliability. Methods and Results: A forward-backward translation was performed based on Sousa's guideline, and then, the face, content, construct validity, internal consistency, and test-retest reliability were tested. Face validity was assessed by five patients, and content validity was evaluated by six experts. Then, construct validity and internal validity were assessed in 107 patients. Finally, test-retest reliability was analyzed in 21 patients. Two items were eliminated following suggestions from the patients and experts. All patients found the scoring system and items clear and relevant. The results showed sufficient content validity index and modified kappa statistics value. Confirmatory factor analysis showed acceptable fit indices. Cronbach's alpha values ranged from 0.67 to 0.95, intraclass correlation coefficient ranged from 0.88 to 0.99, standard error measurement was 2.29-6.15, and the Bland-Altman plot showed an agreement between two test occasions. Conclusion: These results suggested that the Lymph-ICF-UL BM has good validity and reliability in evaluating the QoL of patients with BCRL in Malaysia.

The behavioural effect of short-term cognitive and physical intervention therapies in old dogs

Efforts to counteract age-related decline have resulted in the emergence of various interventions. However, everyday benefits are rarely reported in elderly people. Dogs provide an excellent model for studying aging and interventions due to their similarities to humans. Our aim was to investigate whether a combined physical and cognitive intervention (most effective in humans) could enhance the performance of pet dogs and lead to far transfer effects (improvement in not just the trained specific task). We examined the impact of three-month-long intervention therapies (cognitive, physical, combined) on the cognitive performance and behaviour of old, healthy dogs (N = 72; aged 7.68–14.54 years) using a 12-subtest behavioural test battery. We did not find the combined intervention group outperforming either the cognitive-only or physical-only therapy groups. Physical interventions, either alone or in combination, improved dogs' behavioural flexibility and social behaviour. Cognitive interventions, either alone or in combination, increased neophilia. Furthermore, all intervention therapies made dogs more engaged with their environment. Moreover, less old, around eight years old dogs, exhibited improved social behaviour, problem solving ability, and increased neophilia by their second test occasion. Additionally, dogs' performance was influenced by their health, training, daily play with the owner, and activity/excitability traits. In sum, both cognitive and physical intervention therapies can have an impact on the behaviour of old, healthy pet dogs. However, these therapies may be more effective when longer or applied at a younger age, as the healthy older dogs were less likely to show improvement.

Change of Direction Asymmetry in Youth Elite Tennis Players: A Longitudinal Study.

Longitudinal investigations into the development of inter-limb asymmetry in sports are scarce. This study examined the development of change of direction (COD) asymmetry magnitude in youth elite tennis players. Dominant (overall best performance) and non-dominant (best performance on the other side) scores and COD asymmetry magnitude were quantified annually (up to six years) in 323 male and 235 female players (ages 6 to13 years). Linear mixed effects regression models examined the development of COD performance and asymmetry magnitude according to players' chronological age and sex. Kappa coefficients examined the consistency for the direction of asymmetry across test occasions. Regardless of sex, COD performance significantly improved (p<0.001) while COD asymmetry magnitude significantly decreased (- 0.17±0.87% / year) with increasing chronological age. Regardless of age, males showed significantly lower COD times (- 0.111±0.091 s) and lower COD asymmetry magnitude (- 0.30±1.00%) compared to females. The slight and poor (k-value=0.02-0.00) kappa coefficients for males and females, respectively, highlight the direction specificity of functional asymmetry. These data show that whereas performance of the COD test improved, the magnitude of COD asymmetry declined across chronological age in youth tennis players.

Inter- and intra-session variability of compression strain gauge for the adductor groin squeeze test on soccer athletes.

The importance of hip adductor strength for injury prevention and performance benefits is well documented. The purpose of this study was to establish the intra- and inter-day variability of peak force(PF) of a groin squeeze protocol using a custom-designed compression strain gauge device. Sixteen semi-professional soccer players completed three trials over three separate testing occasions with at least 24-h rest between each session. The main findings were that the compression strain gauge was a reliable device for measuring PF within and between days. All intraclass correlations were higher than 0.80 and coefficients of variations were below 10% across the different sessions and trials. Due to the information gained through the compression strain gauge, the higher sampling frequency utilized, portability, and the relatively affordable price, this device offers an effective alternative for measuring maximal strength for hip adduction.

Validity and Reliability of Force-Time Characteristics Using a Portable Load Cell for the Isometric Midthigh Pull

Abstract Pichardo, AW, Neville, J, Tinwala, F, Cronin, JB, and Brown, SR. Validity and reliability of force-time characteristics using a portable load cell for the isometric midthigh pull. J Strength Cond Res 38(1): 185–191, 2024—Many practitioners use the isometric midthigh pull (IMTP) to assess maximal strength in a safe, time-effective manner. However, expensive, stationary force plates are not always practical in a large team setting. Therefore, the purpose of this study was to establish the validity and between-session reliability of peak force, rate of force development (RFD), and impulse during an IMTP using 2 experimental protocols: a traditional fixed bar with a force plate (BarFP) and a flexible chain measured with a force plate (ChainFP) and a load cell (ChainLC). After a familiarization session, 13 resistance-trained men performed 3 trials of the BarFP condition and 3 trials of the chain-based conditions. The identical procedures were replicated twice more, with a week between each testing session. The main findings were (a) no RFD or impulse measures were found to achieve acceptable reliability across all methodological approaches and testing occasions; (b) peak force was reliable across all methods, with coefficient of variation ranging from 4.6 to 8.3%, intraclass correlation coefficient ranging from 0.94 to 0.98, and the least variability associated with the ChainLC condition; and (c) the ChainFP method was found to significantly underrepresent peak force by 4.8% (p &lt; 0.05), with no significant differences between the ChainLC and BarFP methods. Therefore, the ChainLC would seem a valid, reliable, portable, and cost-effective alternative to force plates when assessing maximal isometric strength in the IMTP.

Relationships between hourly cognitive variability and risk of Alzheimer's disease revealed with mixed-effects location scale models.

Observational studies on aging and Alzheimer's disease (AD) typically focus on mean-level changes in cognitive performance over relatively long periods of time (years or decades). Additionally, some studies have examined how trial-level fluctuations in speeded reaction time are related to both age and AD. The aim of the current project was to describe patterns of variability across repeated days of testing as a function of AD risk in cognitively normal older adults. The current project examined the performance of the Ambulatory Research in Cognition (ARC) smartphone application, a high-frequency remote cognitive assessment paradigm, that administers brief tests of episodic memory, spatial working memory, and processing speed. Bayesian mixed-effects location scale models were used to explore differences in mean cognitive performance and intraindividual variability across 28 repeated sessions over a 1-week assessment interval as function of age and genetic risk of AD, specifically the presence of at least one apolipoprotein E (APOE) ε4 allele. Mean performance on processing speed and working memory was negatively related to age and APOE status. More importantly, e4 carriers exhibited increased session-level variability on a test of processing speed compared to noncarriers. Age and education did not consistently relate to cognitive variability, contrary to expectations. Preclinical AD risk, defined as possessing at least one APOE ε4 allele, is not only associated with mean-level performance differences, but also with increases in variability across repeated testing occasions particularly on a test of processing speed. Thus, cognitive variability may serve as an additional and important indicator of AD risk. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Comparison of Shoulder Rotation Strength and Test-Retest Reliability in 3 Test Positions With Swimmers.

Advancements in portable load-cell technology have enabled high-quality assessment of shoulder internal (IR) and external rotation (ER) peak force (Fmax) and rate of force development (RFD). This study's purpose was to explore the reliability and differences between IR and ER Fmax and RFD in different testing positions using a novel load-cell device. A within-subjects repeated-measures design was employed to compare the intersession values and reliability of Fmax and RFD for both shoulder IR and ER across 3 positions: seated-0°, supine-0° and supine-90°. National-level swimmers (n = 19; age = 16.8 [1.0]y) completed 3 testing occasions of each condition (combination of arm, rotation, and test position) separated by 7 to 14days. IR superseded ER in all testing positions. The association between these positions across IR and ER was typically strong for both Fmax and RFD (r > .85, P < .001) except for IR RFD (r = .56-.73, P < .05). For sessions 2 to 3, Fmax intraclass correlation coefficient and CV (intraclass correlation coefficient = .89-.96, CV = 5.2%-8.8%) were typically within acceptable ranges, whereas RFD (intraclass correlation coefficient = .74-.90, CV = 11.5%-18.1%) often exhibited inflated error. The supine (90°) position was the most consistent position across both measures. Load-cell technology can be confidently used to assess shoulder rotation Fmax in 3 different positions, whereas RFD should be used with caution without protocol refinement.

NINE-YEAR ASSOCIATION OF OPTIMISM AND COGNITIVE FUNCTIONING IN A COHORT OF AGING MEN

Abstract Higher levels of optimism have been linked to better physical and emotional health, and growing evidence suggests optimism may also protect against cognitive impairment and decline. However, our understanding of its prospective associations with cognitive functioning is limited. We examined 9-year associations of optimism with cognitive functioning among 793 men from the VA Normative Aging Study. Optimism was assessed via the Minnesota Multiphasic Personality Inventory-2 in 1986 (baseline: AgeM = 60.1, SD=7.1). Cognitive functioning was measured at participants’ earliest cognitive testing occasion between 1993 and 1996. We considered both global cognition (MMSE) and three domains of cognitive functioning: executive function (verbal fluency via Animal Naming Test, working memory via WAIS-R Digit Span Backward), short-term memory (immediate and delayed CERAD Word List Recall), and visuospatial ability (CERAD and VMI spatial copying, NES-2 Pattern Comparison). Analyses used ordinary least squares regression adjusted for childhood socioeconomic status, and demographics and major diseases at baseline. Optimism was not associated with global cognition. However, higher optimism was associated with better verbal fluency (B=0.48, SE=0.19, 95% CI .11–.86, p=.01) and immediate word list recall (B=0.33, SE=0.15, 95% CI .04–.62, p=.02), and weakly associated with delayed word list recall (B=0.14, SE=0.07, 95% CI -.01–.28, p=.06). Optimism was not associated with visuospatial ability or working memory performance. Our findings suggest that optimism could be particularly important for verbally mediated aspects of executive functioning and memory in aging men. Optimism may be a valuable intervention target to promote healthy cognitive aging.

Trainee psychotherapists’ emotion recognition accuracy during 1.5 years of psychotherapy education compared to a control group: no improvement after psychotherapy training

The ability to recognize and work with patients’ emotions is considered an important part of most psychotherapy approaches. Surprisingly, there is little systematic research on psychotherapists’ ability to recognize other people’s emotional expressions. In this study, we compared trainee psychotherapists’ nonverbal emotion recognition accuracy to a control group of undergraduate students at two time points: at the beginning and at the end of one and a half years of theoretical and practical psychotherapy training. Emotion recognition accuracy (ERA) was assessed using two standardized computer tasks, one for recognition of dynamic multimodal (facial, bodily, vocal) expressions and one for recognition of facial micro expressions. Initially, 154 participants enrolled in the study, 72 also took part in the follow-up. The trainee psychotherapists were moderately better at recognizing multimodal expressions, and slightly better at recognizing facial micro expressions, than the control group at the first test occasion. However, mixed multilevel modeling indicated that the ERA change trajectories for the two groups differed significantly. While the control group improved in their ability to recognize multimodal emotional expressions from pretest to follow-up, the trainee psychotherapists did not. Both groups improved their micro expression recognition accuracy, but the slope for the control group was significantly steeper than the trainee psychotherapists’. These results suggest that psychotherapy education and clinical training do not always contribute to improved emotion recognition accuracy beyond what could be expected due to time or other factors. Possible reasons for that finding as well as implications for the psychotherapy education are discussed.

Survival of experimentally buried large, winged seeds from open sandy habitats defies the established theory of relatedness between seed size, shape, and longevity

Accumulated evidence indicates that species with small, rounded seeds predominantly maintain a persistent soil seed bank, while those having larger and less isodiametric seeds have a transient seed bank. We assumed that species in certain special habitats may be exceptions to this rule. In habitats with sandy soil and open vegetation, the seeds do not necessarily have to penetrate the deeper soil layers through cracks in the soil. Instead, the seeds can become buried by a windblown layer of sand, thus seed morphology does not really affect the burial process. To test our hypothesis, we selected five semi-desert shrubs and one perennial herb of open sandy grasslands, all of which had large and flattened seeds. For each species, 12 repetitions of 50 seeds were buried in the soil. Seeds were recovered after 3, 20 and 26 months of burial and subjected to germination tests. Seeds of each species germinated in all test occasions, with final germination as follows: Atriplex canescens 89.0%, Haloxylon ammodendron 11.5%, H. persicum 11.5%, Pteropyrum aucheri 43.5%, Xylosalsola richteri 12.0% and Asclepias syriaca 26.0%. The results confirm the hypothesis that each of the six species is capable of forming a persistent soil seed bank. The results also show that in habitats where seed burial can take place passively through windblown soil, plant species might bypass the tradeoff between seed size/shape and seed longevity.

Argument-based validation of Academic Collocation Tests

Despite extensive research on assessing collocational knowledge, valid measures of academic collocations remain elusive. With the present study, we employ an argument-based approach to validate two Academic Collocation Tests (ACTs) that assess the ability to recognize and produce academic collocations (i.e., two-word units such as key element and well established) in written contexts. A total of 343 tertiary students completed a background questionnaire (including demographic information, IELTS scores, and learning experience), the ACTs, and the Vocabulary Size Test. Forty-four participants also took part in post-test interviews to share reflections on the tests and retook the ACTs verbally. The findings showed that the scoring inference based on analyses of test item characteristics, testing conditions, and scoring procedures was partially supported. The generalization inference, based on the consistency of item measures and testing occasions, was justified. The extrapolation inference, drawn from correlations with other measures and factors such as collocation frequency and learning experience, received partial support. Suggestions for increasing the degree of support for the inferences are discussed. The present study reinforces the value of validation research and generates the momentum for test developers to continue this practice with other vocabulary tests.

A model-free autonomous performance testing for human recognition using different types of software-intensive autonomous systems

The model-based methods were utilized in order to produce the test cases for the behavioral model of a software system. Run test cases habitually or physically facilitates premature identification of requirement errors. Regression test suite design is thought-provoking as well as significant task in this automated test design. General techniques of regression testing comprise rerunning formerly accomplished tests as well as inspecting whether program behavior has modified as well as formerly fixed faults have recurred. Regression testing is carried out with the intension of assessing a system skillfully by means of logically picking the right least set of tests essential to suitably cover a particular modification. Then again, the relapse testing occasions of experiment prioritization, test suite decrease, and relapse test choice are commonly focused on conditions, which recognize the experiments to pick or the experiment to run thusly in independent framework. As indicated by experiment prioritization, experiments are very much arranged ward upon some condition just as experiments with greatest need are run first to achieve a presentation objective. If there should be an occurrence of test suite decrease/minimization, experiment, which end up being ended over the long haul are dismissed from the test suite with the intension of making a minor arrangement of experiments. In the event of relapse test determination, from a prevalent unique suite, a subset of experiments is picked.

Development of upper and lower extremity functional asymmetries in male and female elite youth tennis players: a longitudinal study.

This longitudinal study aimed to examine the development of both upper and lower extremity functional performances, together with asymmetry magnitudes and directionality in youth tennis players. Dominant and non-dominant physical performance values of 90 players (53 males, 37 females) were determined yearly (with monitoring up to 3 years) using unilateral strength, power, speed and agility tests from which asymmetry magnitude percentages were calculated. Linear mixed effect models examined the development of performance values according to youth players' maturity offset, performance dominance, sex and training volume. Similarly, the development of functional asymmetry magnitudes was examined according to players' maturity offset, sex and training volume. Kappa coefficients (k) examined the consistency in directionality across test occasions. Regardless of sex, the dominant and non-dominant physical performance values of every test significantly (P<0.05) improved with increasing maturity offset. No sex differences were apparent except for strength and power related tests where male players performed significantly better. Functional asymmetry magnitudes (ranging from 2.0 to 15.9%) did not significantly change with increasing maturity offset (range=-0.3-0.4% per year). Training volume was not significantly associated with the performance values and asymmetry magnitudes. The dominant upper extremity (which holds the tennis racket) consistently displayed the dominant performance value (k value: 1.00) across test occasions, which was not the case at lower extremity level (k value range: -0.28-0.31). The functional asymmetry magnitudes did not change significantly with youth tennis players' maturity offset over a 3-year period.

The variability of dual-task walking parameters using in-shoe inertial sensors in nonconcussed individuals: A randomized within-subject repeated measures design.

There is a need for high utility and portability, and cost-effective technologies that are suitable for assessing dual-task gait after experiencing a concussion. Current technologies utilized such as 3D motion capture and force plates are too complex and expensive for most practitioners. The aim of this study was to quantify the variability of dual-task walking gait parameters using in-shoe inertial sensors in nonconcussed individuals. This was a randomized within-subject repeated measures design conducted within a sports laboratory. Twenty healthy, uninjured, nonconcussed participants were recruited for this study. Gait variables of interest were measured across three 2-min continuous walking protocols (12 m, 30 m, 1 min out and back) while performing a cognitive task of counting backward in sevens from a randomly generated number between 300 and 500. Testing was completed over three occasions separated by 7 days, for a total of nine walking trials. Participants completed the testing protocols in a randomized, individual order. The primary outcome was to determine the variability of dual-task walking gait parameters using in-shoe inertial sensors in nonconcussed individuals across three protocols. Three to four participants were allocated to each randomized protocol order. Regarding the absolute consistency (coefficient of variation [CV]) between testing occasions, no gait measure was found to have variability above 6.5%. Relative consistency (intraclass correlation coefficient [ICC]) was acceptable (>0.70) in 95% of the variables of interest, with only three variables < 0.70. Similar variability was found across the three testing protocols. In-shoe inertial sensors provide a viable option for monitoring gait parameters. This technology is also reliable across different testing distances, thus offering various testing options for practitioners. Further research needs to be conducted to examine the variability with concussed subjects.

Puzzling data policy

In the social sciences, the inadequate corona data policy of the Robert Koch Institute (RKI) and the focus on the daily or cumulative number of confirmed Covid 19 cases has been criticised, albeit only sporadically, already in spring 2020. For example, one of the leading statisticians in sociology in Germany, Rainer Schnell - together with Menno Smid of the Infas Institute for Applied Social Science - stated in unsparing clarity at the digital colloquium ‚Sociological Perspectives on the Corona Crisis‘ of the Social Science Research Center Berlin on 15 April 2020 that it was incomprehensible why the RKI would limit itself to absolute reporting incidences of those tested positive without taking into account influencing factors such as test occasions and test frequencies. The RKI also refrained from representative surveys on the incidence of infection and instead relied on unreliable survey instruments. Professional pandemic management is simply not possible without a solid database. These early cautionary recommendations went unheeded instead of shedding light on the darkness of the official data desert on the actual infection rate and individual infection risks.