Clinical Research Directory

Validity and Reliability of a Mixed Reality-Based 6-Minute Walk Test

The 6-Minute Walk Test (6MWT) is a widely used field test for assessing functional exercise capacity, walking endurance, and submaximal performance related to activities of daily living. However, in conventional applications, environmental conditions, observer-related differences, and standardization issues may lead to variability in measurement outcomes. In addition, evaluating only the total walking distance may not adequately reflect clinically important changes such as performance decline and walking-related motor fatigue occurring during the test. For this reason, recent studies have recommended analyzing 6MWT data by dividing the test into minute-by-minute segments and using performance change metrics such as the Distance Walked Index (DWI). These approaches allow a more detailed evaluation of changes in walking performance throughout the test duration. With advances in measurement technologies, mixed reality (MR)-based applications have attracted attention as a means of enabling more objective, standardized, and reproducible implementation of conventional clinical tests. MR technology allows users to maintain interaction with the real environment while receiving digital guidance and feedback, thereby providing a safe and standardized assessment setting. Nevertheless, evidence regarding the validity and reliability of mixed reality-based adaptations of the 6MWT, particularly in asymptomatic adults, remains limited. The aim of this study is to evaluate the criterion validity and test-retest reliability of a mixed reality-based 6-Minute Walk Test (MR-6MWT) developed using the Meta Quest 3 and Unity platform. In addition, convergent validity will be examined by analyzing the relationships between total walking distance, minute-by-minute performance changes, fatigue effect (%), and outcomes of the 4-Meter Walk Test, Timed Up and Go Test, and knee extensor muscle strength. The findings of this study are expected to contribute to the development of a more objective, standardized, and digitally based mixed reality adaptation of the 6MWT. Furthermore, the results may provide a scientific foundation for future remote assessment and digital monitoring applications.

Abbreviated Breast MRI and Digital Tomosynthesis Mammography in Screening Women With Dense Breasts

This randomized phase II trial studies how well abbreviated breast magnetic resonance imaging (MRI) and digital tomosynthesis mammography work in detecting cancer in women with dense breasts. Abbreviated breast MRI is a low cost procedure in which radio waves and a powerful magnet linked to a computer and used to create detailed pictures of the breast in less than 10 minutes. These pictures can show the difference between normal and diseased tissue. Digital tomosynthesis mammography is a procedure that uses multiple x-rays pictures of each breast to produce a 3-dimensional rendering of the entire breast. Combined screening with abbreviated breast MRI and digital tomosynthesis mammography may be a better method to screen women with dense breasts.

New Cardiovascular Risk Screening Strategy.

Mortality due to cardiovascular disease (CVD) in Spain accounted for 29% of all deaths (32% in women and 26% in men) in 2017. Out of those, 67% were related to a coronary or a cerebrovascular disease . A key strategy in primary prevention of CVD is to use risk functions to individualize preventive interventions for each patient. The current CV risk-screening program in some regions of Spain, is based using an adapted Framingham scale, REGICOR's risk function, which is integrated in the primary care electronic health record. This risk function predicts the probability within 10 years of developing a coronary event. However, this function fails to identify patients that fall into low- or intermediate-risk level, and might develop a CV event in the up following 10 years. Ankle-brachial index (ABI) is a simple, non-invasive and economic technique, which allows detecting peripheral arterial disease (PAD), and gives independent risk function information compared to other coronary risk functions. Even tough, between 13-27% of middle age population have an ABI ≤ 9, around 50-89% of them do not exhibit any symptoms. However, they hold higher mortality risk and CV events. Current clinical guidelines for PAD screening, have a limited level of evidence, and only recommend using ABI on patients aged 50-70, who have diabetes or are smokers, and patients older than 70 years old. A new risk function, REASON, to assess CVD risk has been designed. This model has proven to improve predictive capacity of holding an ABI ≤ 0.9 on those patients aged 50-74 that are apparently free of CVD. Therefore, a strategy that combines the current CV risk estimation using REGICOR, and the prediction capacity of pathologic ABI with REASON, would allow detecting high-risk patients with a PAD screening program. It is possible that patients, who hold an ABI ≤ 0.9, even if being asymptomatic, will adopt physician's recommendations on healthy life habits and preventive treatment. The aims of this study are: * To assess the effectiveness and cost-utility of adding a screening program with ABI to the current strategy of CV risk detection to reduce the incidence of CVD and mortality from all causes in the population aged 50 to 74. * To assess the effectiveness of adding a screening program with ABI to the current strategy of CV risk detection to improve cardiovascular risk factors in the population aged 50 to 74.