Refractive features and amblyopia in Duane's Retraction Syndrome: A review of the 582 patients / Características refractivas y ambliopía en el síndrome de retracción de Duane: una revisión de los 582 pacientes

Purpose: To report the visual and refractive characteristics and the prevalence of amblyopia in patients with different types of Duane's Retraction Syndrome (DRS). Method: This retrospective study was performed on hospital records of 582 DRS patients at Farabi Hospital, Iran, from 2012 to March 2022. Results: The mean age of patients was 19.4 ± 11.9 (range, 3–70) years [335 (57.6 %) females and 247 (42.4 %) males (P < .001)]. DRS type I, II, III, and IV were presented in 347 (59.6 %), 148 (25.4 %), 82 (14.1 %), and 5 (0.9 %) patients, respectively. There were 530 (91.1 %) patients with unilateral and 52 (8.9 %) with bilateral involvement. In the unilateral patients, the DRS eyes' corrected distance visual acuity (CDVA) and astigmatism were significantly worse than the Non-DRS Eyes (P < .001). The mean amount of all refractive and visual parameters in bilateral patients' right or left eyes was significantly lower than in unilateral patients' non-DRS eyes (all P < .05). Anisometropia was observed in 75(12.9 %) of the patients. Amblyopia was observed in 18.5 % (98 patients) and 36.5 % (19 patients) of unilateral and bilateral DRS patients, respectively (P < .001). In unilateral patients, amblyopia was found in 57 (16.4 %) patients with Type I, 22 (14.9 %) patients with Type II, 16 (19.5 %) patients with Type III, and 3 (60 %) patients with Type IV. Forty-four (37.6 %) of patients with amblyopia had anisometropia. Conclusion: This large-scale study indicates that DRS types differ in terms of refractive error, visual acuity, and the prevalence of amblyopia and anisometropia. Clinicians should be aware of the clinical features associated with different types of DRS.(AU)

Mean cycloplegic refractive error in emmetropic adults – The Tehran Eye Study / Error refractivo ciclopléjico medio en adultos emétropes: estudio ocular de Teherán

Purpose: In children under 20 years, refractive development targets a cycloplegic refractive error of +0.5 to +1.5D, while presbyopes over 40 years generally have non-cycloplegic errors of ≥ +1D. Some papers suggest these periods are separated by a period of myopic refractive error (i.e., ≤ –0.50D), but this remains unclear. Hence, this work investigates the mean cycloplegic refractive error in adults aged between 20 – 40 years. Methods: In 2002 a cross-sectional study with stratified cluster sampling was performed on the population of Tehran, providing cycloplegic and non-cycloplegic refractive error data for the right eyes of 3,576 participants, aged 30.6 ± 18.6 years (range: 1–86 years). After grouping these data into age groups of 5 years, the refractive error histogram of each group was fitted to a Bigaussian function. The mean of the central, emmetropized peak was used to estimate the mean refractive error without the influence of myopia. Results: The mean cycloplegic refractive error at the emmetropized peak decreased from +1.10 ± 0.11D (95 % confidence interval) to +0.50 ± 0.04D before 20 years and remains stable at that value until the age of 50 years. The non-cycloplegic refractive error also sees a stable phase at 0.00 ± 0.04D between 15 – 45 years. After 45 – 50 years both cycloplegic and non-cycloplegic refractive error become more hypermetropic over time, +1.14 ± 0.12D at 75 years. Conclusions: The cycloplegic refractive error in adults is about +0.50D between 20 – 50 years, disproving the existence of the myopic period at those ages.(AU)

Dispensing Errors and Self-medication Practices-Pharmacists' Experience in Tabuk: A Cross-sectional Study.

Background: Community pharmacists are engaged in various professional activities starting from drug dispensing to promoting the well-being of patients. They dispense medications as stated in the prescription and are also licensed to prescribe over-the-counter (OTC) medications. Self-medication is widely practiced in various countries, which may lead to irrational drug use. The objectives of this study were to identify the factors associated with dispensing errors, to find ways to minimize dispensing errors, to identify patients' reasons for self-medication, and to find the drugs commonly utilized by patients as OTC medications and the sources of their drug information. Methods: A cross-sectional survey of a convenience sample of 286 registered community pharmacists all over Tabuk was conducted using a self-administered questionnaire. Results: Physician's unclear handwriting in the prescription was the major factor for dispensing error (2.6 out of 3) and writing the prescription clearly by the physician or using a printed form of prescription was an important factor in minimizing dispensing errors (2.91 out of 3). Previous similar complaints in the past were the main reason for self-medication (2.45 out of 3) with analgesics and antipyretics being the commonly dispensed drug groups dispensed as OTC medications (2.95 out of 3). Conclusion: Self-medication practices and dispensing errors are widespread in Tabuk. Antibiotics were dispensed as OTC medication, which may lead to more chance of irrational drug use. Writing the prescription clearly and legibly would reduce dispensing errors. It is the community pharmacists' responsibility to increase awareness regarding the appropriate use of drugs to the public.

Research on high-speed digital optical signal jitter measurement technology based on clock recovery algorithm using eye diagram opening area.

With the rapid development of information technology, high-speed digital optical signal transmission technology has become the core of modern communication networks. However, the increase in transmission rates brings challenges such as noise, distortion, and interference, which affect the accuracy of clock recovery. To address these issues, this study proposes a clock recovery algorithm based on the eye diagram opening area to improve the accuracy and efficiency of high-speed digital optical signal jitter measurement. The proposed method extracts clock information from the signal using the opening area and curvature characteristics of the eye diagram for jitter measurement. Experimental results demonstrate that the clock recovery algorithm based on the eye diagram opening area can stably reconstruct the signal eye diagram and obtain jitter parameters under different optical power conditions. At optical powers of -7.2 dBm, -12.2 dBm, and -17.2 dBm, the Q-factors were 8.8, 7.6, and 4.3, respectively, and the RMS jitter values were 12.2 ps, 13.4 ps, and 21.2 ps, respectively. At optical powers of -2.3 dBm, 0.1 dBm, 2.4 dBm, 4.6 dBm, and 6.0 dBm, the Q-factors were 9.1, 9.3, 9.5, 9.7, and 10.0, respectively, and the average jitter values were 8.9 ps, 8.5 ps, 8.0 ps, 7.5 ps, and 7.0 ps. These results indicate that the proposed algorithm performs excellently under low optical power conditions and maintains high recovery accuracy even when jitter increases at higher optical powers. The clock recovery algorithm based on the eye diagram opening area significantly improves the accuracy and stability of high-speed digital optical signal jitter measurement, enriches the theoretical research of clock recovery algorithms, and shows significant advantages in improving signal transmission quality, reducing bit error rate, and enhancing communication link reliability. The research outcomes provide key technical support for the optimization of modern high-speed optical communication systems.

AFFECT: an R package for accelerated functional failure time model with error-contaminated survival times and applications to gene expression data.

BACKGROUND: Survival analysis has been used to characterize the time-to-event data. In medical studies, a typical application is to analyze the survival time of specific cancers by using high-dimensional gene expressions. The main challenges include the involvement of non-informaive gene expressions and possibly nonlinear relationship between survival time and gene expressions. Moreover, due to possibly imprecise data collection or wrong record, measurement error might be ubiquitous in the survival time and its censoring status. Ignoring measurement error effects may incur biased estimator and wrong conclusion. RESULTS: To tackle those challenges and derive a reliable estimation with efficiently computational implementation, we develop the R package AFFECT, which is referred to Accelerated Functional Failure time model with Error-Contaminated survival Times. CONCLUSIONS: This package aims to correct for measurement error effects in survival times and implements a boosting algorithm under corrected data to determine informative gene expressions as well as derive the corresponding nonlinear functions.

Characteristics of astigmatism in school-age children aged 5 to 13 years in northeast Sichuan: a cross-sectional school-based study.

Background: Astigmatism is closely associated with myopia progression, vision loss, eye fatigue and amblyopia, which seriously endangers children's eye health. This study aims to investigate the prevalence and characteristic distribution of astigmatism in children in Langzhong City, providing valuable insights for allocating resources and develop prevention and control strategies. Methods: A cross-sectional study and random sampling survey were conducted. Between January and November 2021, 21,415 students aged 5 to 13 years from 14 primary schools in Langzhong City underwent non-cycloplegic refractive testing using autorefraction. The data on myopia were analyzed using SPSS (Statistical Package for the Social Sciences) version 23.0. Results: The inclusion criterion was set at an absolute astigmatism value of ≥0.50D. Among the 21,415 children studied, 61.70% were found to have astigmatism. The prevalence of astigmatism varied significantly across different grades (χ2=501.414, P<0.001). The predominant types of astigmatism were mild astigmatism (0.50-1.00D) and with-the-rule astigmatism. Mixed astigmatism was primarily observed in children in grades 1 and 2, while compound myopic astigmatism was more common in children in grades 3 to 6. These differences were statistically significant. As the degree of astigmatism increased, the proportions of against-the-rule astigmatism, oblique astigmatism, compound myopic astigmatism, and simple hyperopic astigmatism decreased, whereas the proportions of with-the-rule astigmatism, mixed astigmatism, and compound hyperopic astigmatism increased. Conclusions: The prevalence of astigmatism among school-age children aged 5 to 13 years in northeast Sichuan is notably high, with compound myopic astigmatism and with-the-rule astigmatism being the most common types. Regular refractive examinations are crucial for the early detection and management of astigmatism.

Human error identification and risk assessment in loading and unloading of petroleum products by road trucks using the SHERPA and fuzzy inference system method.

Human error constitutes one of the primary causes of accidents, particularly in the context of loading and unloading operations involving road trucks, especially those carrying petroleum products. The process of identifying and evaluating human errors within these operations involves several key steps. Initially, all sub-tasks associated with loading and unloading are meticulously identified and analyzed utilizing Hierarchical Task Analysis (HTA), achieved through direct observation, document examination, and interviews. Subsequently, potential human error modes within each task are delineated using the Systematic Human Error Reduction and Prediction Approach (SHERPA). Finally, essential data for determining the criticality, probability, and severity of each error are gathered through expert elicitation and the application of Fuzzy Inference Systems (FIS). Through the analysis of SHERPA worksheets, a total of 37 errors during loading operations and 14 errors during unloading operations of petroleum products were identified. Among these errors, the predominant category during loading operations was action errors, comprising 31 instances, while communication errors were the least frequent, occurring only twice. Similarly, action errors were most prevalent during unloading operations, constituting 13 instances. These errors were further categorized and ranked based on their risk levels, resulting in 27 levels for loading operations and 12 levels for unloading operations. The consistent occurrence of action errors underscores the need for implementing control measures to mitigate their frequency and severity. Such strategies may include periodic training sessions to reinforce proper work procedures and the development of monitoring checklists, among other interventions.

Uncertainty in river discharge forcings and error range on nowcasting numerical simulation of salinity and seawater temperature in Ise Bay, Japan.

We estimated the error range of the simulated salinity and seawater temperature based on the uncertainty of the river discharge into Ise Bay in a nowcasting numerical simulation model. We used two methods for calculating the river discharge forcing. In the first method, precipitation was used as the input for the storage function method. In the second method, the Basin Rainfall Index was used, which is a nowcasting dataset of river discharge simulated by the Japan Meteorological Agency. The uncertainty in annual river discharge in both methods was estimated to be within ±30 %. Simulations were conducted using the hydrodynamic simulation model. Annual simulation error ranges associated with the uncertainty in river discharge for salinity and seawater temperature were estimated to be approximately ±1.2 and ±0.15 °C, respectively. We proposed a practical research procedure that can be applied to other models and the simulation of the water environment of coastal and estuary areas.

Impact of day-to-day variation in FEV1 on measures of change: A conceptual description.

Clinical trials often demonstrate treatment efficacy through change in forced expiratory volume in one second (FEV1), comparing single FEV1 measurements from post- versus pre-treatment timepoints. Day-to-day variation in measured FEV1 is common for reasons such as diurnal variation and intermittent health changes, relative to a stable, monthly average. This variation can alter estimation of associations between change in FEV1 and baseline in predictable ways, through a phenomenon called regression to the mean. We quantify and explain day-to-day variation in percent-predicted FEV1 (ppFEV1) from 4 previous trials, and we present a statistical, data-driven explanation for potential bias in ceiling and floor effects due to commonly observed amounts of variation. We recommend accounting for variation when assessing associations between baseline value and change in CF outcomes in single-arm trials, and we consider possible impact of variation on conventional standards for study eligibility.

Enhanced humidity sensing properties of Ta2O5 and ITO doped rutile-TiO2 porous ceramics.

In this study, we investigated the humidity sensing properties of TiO2-based ceramics doped with tantalum pentoxide (Ta2O5) and indium tin oxide (ITO). Pure TiO2, 1%Ta-doped TiO2 (1%TTO), 1%ITO-doped TiO2 (1%ISTO), and 1%(Ta2O5 + ITO) co-doped TiO2 (1%ISTTO) ceramic samples were obtained by sintering at 1200 °C for 3 h. The rutile phase was observed in all samples. The lattice parameters of the single and co-doped samples were larger than those of pure TiO2, confirming the substitution of dopants. Porosity was observed in all ceramics. The mean grain sizes of all doped samples were significantly reduced compared to undoped TiO2. A homogeneous element dispersion was observed in the 1%TTO and 1%ISTTO ceramics, while segregation particles of related In-rich elements was observed in the 1%ISTO ceramic. Giant dielectric properties were not achieved in any samples due to the porosity. Nevertheless, excluding the undoped TiO2, the dielectric properties of all porous ceramics varied significantly with changes in humidity. The 1%ISTTO ceramic demonstrated superior humidity sensing properties, including a low maximum hysteresis error of 3.6% at 102 Hz. In contrast, the 1% TTO and 1% ISTO ceramics showed higher maximum hysteresis errors of 7.2% and 19.8%, respectively. Notably, the response and recovery times were 7.05 ± 0.18 and 2.48 ± 0.39 min, respectively, with good repeatability. This improvement is likely due to the synergistic effect of oxygen vacancies and Ta Ti · defects on the surface, enhancing the humidity sensing properties of the 1% ISTTO ceramic, coupled with its optimal microstructure due to its lowest porosity and grain size.

From Pregnancy Pains to Paralysis: An Erroneous Intrathecal Digoxin Administration Case Report and Review of Medical Errors.

Digoxin is a Na-K ATPase inhibitor commonly used to treat heart failure and atrial fibrillation. It is only approved for oral or intravenous (IV) use. There is no approved indication for intrathecal administration. Only four previously reported cases of intrathecal digoxin administration in pregnant patients are in the literature. We present a patient who had an unfortunate case of erroneous intrathecal Digoxin administration following an elective Cesarean section. Post-delivery, the patient's mental status deteriorated. She became unresponsive and remained comatose for 11 days. Brain magnetic resonance imaging (MRI) showed diffuse, patchy hyperintensities involving bilateral frontotemporal lobes and basal ganglia. A spine MRI showed extensive cervical and thoracic cord edema. At discharge, the patient was paraplegic with no sensation or motor response below the level of T10. At the 90-day follow-up, she had intact mental status and minimal improvement in motor strength and sensation below T10 and was reportedly breastfeeding. This is an unfortunate case of severe neurological deficits resulting from a grave medical error, which continues to be a prevalent issue in the United States healthcare system.

Iterative Data-adaptive Autoregressive (IDAR) whitening procedure for long and short TR fMRI.

Introduction: Functional magnetic resonance imaging (fMRI) has become a fundamental tool for studying brain function. However, the presence of serial correlations in fMRI data complicates data analysis, violates the statistical assumptions of analyses methods, and can lead to incorrect conclusions in fMRI studies. Methods: In this paper, we show that conventional whitening procedures designed for data with longer repetition times (TRs) (>2 s) are inadequate for the increasing use of short-TR fMRI data. Furthermore, we comprehensively investigate the shortcomings of existing whitening methods and introduce an iterative whitening approach named "IDAR" (Iterative Data-adaptive Autoregressive model) to address these shortcomings. IDAR employs high-order autoregressive (AR) models with flexible and data-driven orders, offering the capability to model complex serial correlation structures in both short-TR and long-TR fMRI datasets. Results: Conventional whitening methods, such as AR(1), ARMA(1,1), and higher-order AR, were effective in reducing serial correlation in long-TR data but were largely ineffective in even reducing serial correlation in short-TR data. In contrast, IDAR significantly outperformed conventional methods in addressing serial correlation, power, and Type-I error for both long-TR and especially short-TR data. However, IDAR could not simultaneously address residual correlations and inflated Type-I error effectively. Discussion: This study highlights the urgent need to address the problem of serial correlation in short-TR (< 1 s) fMRI data, which are increasingly used in the field. Although IDAR can address this issue for a wide range of applications and datasets, the complexity of short-TR data necessitates continued exploration and innovative approaches. These efforts are essential to simultaneously reduce serial correlations and control Type-I error rates without compromising analytical power.

The effectiveness of checklists and error reporting systems in enhancing patient safety and reducing medical errors in hospital settings: A narrative review.

Objectives: This narrative review aimed to explore the impact of checklists and error reporting systems on hospital patient safety and medical errors. Methods: A systematic search of academic databases from 2013 to 2023 was conducted, and peer-reviewed studies meeting inclusion criteria were assessed for methodological rigor. The review highlights evidence supporting the efficacy of checklists in reducing medication errors, surgical complications, and other adverse events. Error reporting systems foster transparency, encouraging professionals to report incidents and identify systemic vulnerabilities. Results: Checklists and error reporting systems are interconnected. Interprofessional collaboration is emphasized in checklist implementation. In this review, limitations arise due to the different methodologies used in the articles and potential publication bias. In addition, language restrictions may exclude valuable non-English research. While positive impacts are evident, success depends on organizational culture and resources. Conclusions: This review contributes to patient safety knowledge by examining the relevant literature, emphasizing the importance of interventions, and calling for further research into their effectiveness across diverse healthcare and cultural settings. Understanding these dynamics is crucial for healthcare providers to optimize patient safety outcomes.

Disaggregation of Dairy in Composite Foods in the United Kingdom.

Dairy, especially cheese, is associated with high levels of greenhouse gas emissions. Accurate estimates of dairy consumption are therefore important for monitoring dietary transition targets. Previous studies found that disaggregating the meat out of composite foods significantly impacts estimates of meat consumption. Our objective was to determine whether disaggregating the dairy out of composite foods impacts estimates of dairy consumption in Scotland. Approximately 32% of foods in the UK Nutrient Databank contain some dairy. In the 2021 Scottish Health Survey, mean daily intakes of dairy with and without disaggregation of composite foods were 238.6 and 218.4 g, respectively. This translates into an 8% underestimation of dairy consumption when not accounting for dairy in composite foods. In particular, milk was underestimated by 7% and cheese and butter by 50%, whereas yogurt was overestimated by 15% and cream by 79%. Failing to disaggregate dairy from composite foods may underestimate dairy consumption.

Establishing and Validating Refractive Error Reference Values for Myopia Prediction Among Children Aged 6-12 Years - Jiangsu Province, China, 2018-2023.

What is already known about this topic?: Previously, it has been proved that a simplified model that uses refraction error value provides a robust and efficient means of predicting myopia for non-myopic students. Intervention targeting non-myopic children with alert refraction errors (or insufficient hyperopia reserve) holds significant importance in reducing the incidence rate of myopia. What is added by this report?: This study, comprising two phases (surveillance and cohort studies), was aiming to pinpoint the precise refractive error value for the onset of myopia prediction among non-myopic children in Jiangsu Province. What are the implications for public health practice?: First, when conducting myopia screenings using pupil dilation for non-myopic populations: the cycloplegic 50th percentile refractive error emerges as a more precise predictive indicator. Second, when conducting myopia screenings without pupil dilation: this study advocates for the incorporation of axial length (AL) and corneal curvature (CC) values as supplementary indicators in screenings.

Adverse events and perceived abandonment: learning from patients' accounts of medical mishaps.

BACKGROUND: Adverse medical events affect 10% of American households annually, inducing a variety of harms and attitudinal changes. The impact of adverse events on perceived abandonment by patients and their care partners has not been methodically assessed. OBJECTIVE: To identify ways in which providers, patients and families responded to medical mishaps, linking these qualitatively and statistically to reported feelings of abandonment and sequelae induced by perceived abandonment. METHODS: Mixed-methods analysis of responses to the Massachusetts Medical Errors Recontact survey with participants reporting a medical error within the past 5 years. The survey consisted of forty closed and open-ended questions examining adverse medical events and their consequences. Respondents were asked whether they felt 'that the doctors abandoned or betrayed you or your family'. Open-ended responses were analysed with a coding schema by two clinician coders. RESULTS: Of the 253 respondents, 34.5% initially and 20% persistently experienced abandonment. Perceived abandonment could be traced to interactions before (18%), during (34%) and after (45%) the medical mishap. Comprehensive post-incident communication reduced abandonment for patients staying with the provider associated with the mishap. However, 68.4% of patients perceiving abandonment left their original provider; for them, post-error communication did not increase the probability of resolution. Abandonment accounted for half the post-event loss of trust in clinicians. LIMITATIONS: Survey-based data may under-report the impact of perceived errors on vulnerable populations. Moreover, patients may not be cognizant of all forms of adverse events or all sequelae to those events. Our data were drawn from a single state and time period. CONCLUSION: Addressing the deleterious impact of persisting abandonment merits attention in programmes responding to patient safety concerns. Enhancing patient engagement in the aftermath of an adverse medical event has the potential to reinforce therapeutic alliances between patients and their subsequent clinicians.

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Inborn errors of immunity (IEI) are a diverse group of disorders caused by defects in immune system structure or function, involving both innate and adaptive immunity. The 2022 update of the IEI classification includes 485 distinct disorders, categorized into ten major disease groups. With the rapid development of molecular biology, the specific pathogenesis of many IEI has been revealed, making gene therapy possible in preclinical and clinical research of this type of disease. This article reviews the advancements in gene therapy for IEI, aiming to increase awareness and understanding of these disorders.

Landing error scoring system: A scoping review about variants, reference values and differences according to sex and sport.

OBJECTIVE: The Landing Error Scoring System (LESS) is a movement analysis tool proposed to identify the risk of anterior cruciate ligament injuries, very useful for injury prevention. The aim of this study is to review the variants of the LESS, their normative scores and the differences according to sex and sport practiced. METHODS: PubMed, Scopus and ScienceDirect databases were searched from inception to October 19, 2023. Studies were eligible if the objective was finding normative or reference scores for the LESS, analyze the differences between sexes or sports, or used some variant of the test. Results were limited to available full-text articles published in English in peer-reviewed journals. RESULTS: Of the 360 articles identified, 20 were included for a full analysis (18,093 participants, age = 8-30 years, males = 70.6%). The military population was the most frequently analyzed (7 studies, n = 16,603). Results showed six variants of the LESS and average values ranged from 2.56 to 7.1. Males and females showed different pattern landing with errors in different planes. CONCLUSIONS: Our findings highlight the need for more field studies on LESS reference scores, particularly for females and basketball or hockey players. Further research is required before conducting a systematic review and meta-analysis.

Precision of trunk movement in people with chronic low back pain.

BACKGROUND: Motor control exercise is commonly applied in people with chronic low back pain (CLBP), but possibly not all people with CLBP have motor control impairments. We suggest movement precision as measure to identify motor control impairments. Movement precision has been operationalized as trunk movement variability (TMV) and as trunk tracking error(s) (TTE). OBJECTIVES: To compare the known-group validity and the responsiveness of TMV and TTE. DESIGN: We used a case-control comparison (Healthy controls (n = 30) vs CLBP (n = 60)) to assess the known-group validity. A cohort study, (measurements in week 3 and week 12 of treatment), was used to assess responsiveness. METHODS: TMV (temporal (CyclSD) and spatial (MeanSD)) was analyzed during standing, repetitive flexion and rotation tasks (35x). TTE was measured during movement target tracking tasks, again in flexion and rotation. Participants with CLBP followed a multidisciplinary intervention and both measures were assessed in week 3 and week 12 of treatment. 2-way MANOVA and 2-way ANOVA were used to assess the effect of Group (CLBP vs healthy controls) and direction (flexion vs rotation) on TMV and TTE. For responsiveness, 2-way MANOVA and 2-way ANOVA were used to assess the effect of treatment and direction on both measures. FINDINGS: At baseline, TMV was not different between groups, while TTE was higher in the people with CLBP (p = 0.005, np2 = 0.09). Treatment strongly decreased temporal TMV (p = 0.025, np2 = 0.33) and TTE (p < 0.001, np2 = 0.844). CONCLUSIONS: These results demonstrate that TTE is more sensitive to CLBP and more responsive to treatment than TMV.

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.