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48 clinical studies listed.

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Biomarkers

Tundra lists 48 Biomarkers clinical trials. Each listing includes eligibility criteria, study locations, and direct links to research sites in the Tundra directory.

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NOT YET RECRUITING

NCT07709247

Salivary Cytokines, MMP-8 and Dental Caries in Osteoporosis Patients

This study examines saliva samples from patients with osteoporosis. The levels of cytokines and Matrix Metalloproteinase-8 (MMP-8) enzyme in saliva will be measured. Additionally, the dental caries status of participants will be evaluated. The aim of this study is to understand the relationship between osteoporosis and oral health. Only saliva samples will be collected from participants; no treatment or medication will be administered.

Gender: All

Ages: 45 Years - 75 Years

Updated: 2026-07-16

Osteoporosis
Dental Caries
Biomarkers
+1
NOT YET RECRUITING

NCT07702500

Multimodal Analysis of Early Biomarkers of the Impacts of Perinatal Asphyxia

Current diagnostic methods rely primarily on clinical symptoms, supplemented by brain imaging and physiological tests. However, these signs of injury only become apparent once significant damage has occurred, thus delaying intervention and compromising the effectiveness of treatments. Therefore, there is a need to develop new markers to develop preventive measures for the consequences of perinatal asphyxia. The primary objective is to compare cognitive and motor development at 18 months in three populations (PA, at risk of PA, and Control) defined on the basis of clinical, biological, and neural criteria.

Gender: All

Ages: 1 Day - Any

Updated: 2026-07-14

Neonate
Asphyxia
EEG
+2
NOT YET RECRUITING

NCT07696156

Immersive VR to Reduce Stress, Anxiety, and Pain During PICC/Midline Placement

Medical and technological advancements allow increasingly complex invasive procedures to be performed on hospitalized patients, improving their survival rates and prognosis. However, these interventions impact physical, emotional, and psychological health. In this scenario, post-hospitalization syndrome (PHS) emerges as a concerning phenomenon characterized by functional, emotional, and social decline after discharge. Invasive procedures such as surgeries or prolonged use of catheters not only compromise physical integrity but also contribute to disorders like anxiety, depression, and post-traumatic stress. In fact, between 20% and 30% of patients admitted to the Intensive Care Unit (ICU) develop symptoms compatible with post-traumatic stress disorder. This underscores the need for a comprehensive approach focused on psychological and social well-being during and after the hospital stay. Despite humanization initiatives, few hospitals successfully implement them due to a lack of objective evaluations and clinical recommendations that justify their necessity. In this regard, venous catheterization (VC) is the most prevalent invasive procedure. The pain, anxiety, or fear caused by this technique triggers physiological and psychological alterations that can interfere with the successful insertion of the device. This stress response induces vasoconstriction, reducing the caliber of the vein, which increases technical difficulty, elevates the risk of complications, raises healthcare costs, and negatively impacts patient satisfaction. Natural outdoor environments have been shown to reduce stress, enhancing well-being and health in the general population. In this sense, the use of immersive virtual reality (IVR) to achieve immersion in virtual nature could help not only by diverting attention away from the painful or anxiety-inducing stimulus during invasive procedures but also by providing pleasant stimuli that could have a physiological impact. The objective of this study is to evaluate the impact of IVR on stress and anxiety during VC using validated clinical scales, measuring the caliber of the vessel to be punctured, and determining salivary biomarkers of stress, well-being, and pain. Confirming this hypothesis will provide the evidence to integrate virtual reality into the National Health System as a standard tool for more humanized and innovative care.

Gender: All

Ages: 18 Years - Any

Updated: 2026-07-10

2 states

Vasoconstriction
Biomarkers
Central Venous Catheters
+6
NOT YET RECRUITING

NCT07675018

INterest of the Negative Predictive Value of Integrons in the reduCtion of Large Broad-spectrum anTibiotics Consumption for Urinary Tract infectionS

Urinary tract infections (UTI), mainly driven by Gram-negative bacteria (GNB) are a frequent cause of hospitalization and the second cause of antibiotic prescription after lower respiratory tract infections. Integrons play a major role in the dissemination of antibiotic resistance among GNB. In the prospective INVICTUS project, whose ultimate objective is to reduce the use of large broad-spectrum antibiotics, our hypothesis is that, in adult patients with a non-severe UTI (qSOFA\<2) and a former documentation with a 3GC-resistant GNB in the previous 6 months, integrons search could reduce the empirical use of large broad-spectrum antibiotics.

Gender: All

Ages: 18 Years - Any

Updated: 2026-07-01

Drug Resistance, Microbial
Biomarkers
Urinary Tract Infections (UTI's)
+1
COMPLETED

NCT05621863

Fruit and Vegetable Biomarker Discovery

The purpose of this research is to find a set of markers in the blood and/or urine that can be linked to consumption of specific fruits and vegetables. This will allow for better understanding of the link between diet and health-related outcomes. Furthermore, the results of this study will lead to the development of new methods to evaluate the nutritional status of individuals in both community and clinical settings. Food frequency questionnaires and diaries/recalls can be affected by intentional or unintentional misreporting, and thus can create errors in determining nutritional status. This study will lead to the development of an objective way to assess the consumption of specific fruits and vegetables by the general population.

Gender: All

Ages: 18 Years - Any

Updated: 2026-05-29

1 state

Biomarkers
RECRUITING

NCT07611136

Cerebral Small Vessel Disease Progression Dependent on Stroke Type

The goal of this prospective, observational study is to understand if cerebral small vessel disease (CSVD) has different velocities and patterns of temporal development, dependent on a concurrent ischemic stroke. It focusses on adult patients with known or newly diagnosed CSVD on magnetic resonance imaging. The study will evaluate if blood based, in parts central nervous system specific protein markers, so called biomarkers, have an additional value reflecting the course of CSVD as defined per MRI assessments. Further patient-relevant endpoints include neuropsychological abilities, neurological functional outcomes, quality of life assessments, stroke recurrence risk.

Gender: All

Ages: 18 Years - Any

Updated: 2026-05-28

1 state

Cerebral Small Vessel Disease
Stroke
Stroke Recurrence
+1
ACTIVE NOT RECRUITING

NCT07599540

Cardiovascular Risk in Peripheral Artery Disease Patients Undergoing Endovascular Revascularisation

This study will investigate heart-related complications in patients with peripheral arterial disease (PAD) undergoing endovascular revascularization procedures to improve blood flow in the legs. Previous studies have shown that some patients develop silent heart injury after these procedures, even without symptoms, and that this may be associated with worse long-term outcomes. Approximately 500 patients will be included in the study. Blood tests for cardiac biomarkers, including high-sensitivity troponin and NT-proBNP, will be performed before and after the procedure. Participants will also undergo ultrasound examination of the heart to assess heart function, including advanced measures that may detect early or subtle heart damage. In addition, heart rate variability will be measured using a short electrocardiogram recording. Patients will be followed for 30 days and 1 year after the procedure to assess the occurrence of major cardiovascular events, limb-related complications, and death. Additional blood samples will be collected and stored for future analysis of inflammation, oxidative stress, and genetic markers that may help explain the mechanisms associated with heart injury and prognosis in these patients.

Gender: All

Updated: 2026-05-20

Peripheral Arterial Disease
Myocardial Injury
Troponin
+6
RECRUITING

NCT07574359

RUSS-AGE: Creating of a Biological Age Calculator and Study of Aging Phenotypes in the Russian Population

This is a multi-center, cross-sectional, observational study aimed at developing biological age calculators specifically for the Russian population investigating various aging phenotypes. Aging is a complex process that varies greatly between individuals, meaning that chronological age does not always reflect one's biological health status. The primary goal of this study is to identify and analyze a comprehensive set of markers (including socioeconomic factors, lifestyle, physical parameters, cognitive function, and laboratory biomarkers) that best reflect the aging process. Using this data, researchers will create a mathematical model to estimate a person's "biological age." The study plans to enroll at least 3,500 male and female volunteers aged 18 years and older from across Russia. Participants will be divided into 5-year age groups (e.g., 18-24, 25-29, up to 90+ years) to ensure broad representation. Participation involves a single visit to a clinical center. During this visit, participants will undergo: Interview and questionnaires (assessing health history, lifestyle, socioeconomic status, diet, sleep, and quality of life). Physical examination and anthropometric measurements (height, weight, blood pressure, grip strength). Functional and cognitive tests (e.g., walking speed, balance tests, memory and attention tasks tailored to age). Collection of biomaterials: blood (50 ml), urine, and stool samples for extensive laboratory analysis, including routine tests and specialized aging biomarkers. Part of the biomaterials will be biobanked for future scientific research. Instrumental examinations for a subset of participants: Depending on the center's capabilities and the study protocol, some participants may also undergo additional assessments such as densitometry (bone density scan), bioimpedance analysis (body composition), and brain MRI. The results are expected to lead to the creation of a validated biological age calculator for the Russian population. This tool could help identify targets for interventions to promote healthy aging and, in the future, potentially predict the risk of developing age-related chronic diseases.

Gender: All

Ages: 18 Years - Any

Updated: 2026-05-07

Healthy Aging
Biomarkers
NOT YET RECRUITING

NCT07562243

Project PHOENIX: Molecular Signatures of Burn Pit Exposure

Project PHOENIX is an observational clinical research study designed to characterize molecular, genomic, cellular, and functional features in blood specimens from former U.S. Service Members with prior burn pit exposure and from matched unexposed controls. Participants will complete screening, informed consent, health and exposure questionnaires, and a one-time blood collection. Blood-derived specimens may undergo genomic, epigenomic, transcriptomic, proteomic, metabolomic, immunophenotyping, and cellular functional analyses. Participants may also agree to optional future re-contact for health updates and possible repeat blood collection. The goal is to identify biologic signatures associated with prior deployment-related burn pit exposure and to support future biomarker discovery and translational research in veteran health.

Gender: All

Ages: 18 Years - Any

Updated: 2026-05-01

Burn Pit Exposure
Airborne Hazard Exposure
Veteran Health
+4
COMPLETED

NCT07542353

Clinical Impact of Different Crystalloid Solution on Early Biomarkers of Kidney Injury After Lumbar Fusion Surgery in Elderly Patients

This study aims to compare the effects of sodium acetate Ringer's solution versus sodium lactate Ringer's solution on early postoperative renal function indicators, renal injury biomarkers, and acute kidney injury (AKI) in elderly patients undergoing lumbar fusion surgery.

Gender: All

Ages: 65 Years - 80 Years

Updated: 2026-04-21

Lumbar Fusion Surgery
Elderly Patients
Sodium Acetate Ringer's Solution
+3
NOT YET RECRUITING

NCT07504861

Biomarkers in Apical Periodontitis

Aim: To evaluate the effects of three different irrigation activation techniques-conventional syringe irrigation (CSI), ultrasonic irrigation (UI), and SWEEPS (Shock Wave Enhanced Emission Photoacoustic Streaming)-on the levels of proinflammatory cytokines (Tumor Necrosis Factor Alpha (TNF-α), interleukin-1beta (IL-1β)) and proteolytic enzymes matrix metalloproteinase-9 (MMP-9) in teeth with chronic apical periodontitis. Methodology: Sixty-six male patients (aged 18-35) with single-rooted teeth, previous root canal treatment (at least 4 years ago), and periapical lesions (\<1 cm, PAI score 3 or 4) were included. Sample size was determined by G\*Power (Power=0.90, α=0.05). Following local anesthesia and rubber dam isolation, endodontic access was performed under a dental operating microscope. After removing old filling material and completing root canal preparation with Reciproc R25/R50 files, patients were randomly assigned into three groups (n=22 each): (1) CSI (30G needle), (2) UI (EMS miniPiezon), and (3) SWEEPS (Er:YAG laser, 2940 nm). Periapical exudate samples were collected using sterile paper points (2 mm beyond the apex for 60s) at the first visit (pre-treatment) and the second visit (one week post-medication with calcium hydroxide). Samples were analyzed via ELISA for TNF-α, IL-1β, and MMP-9 levels. Statistical Analysis: Data were analyzed using IBM SPSS 20. Percent changes in biomarker levels were evaluated using the Kruskal-Wallis test for inter-group comparisons and the Wilcoxon test for intra-group (pre- vs. post-treatment) comparisons. Linear regression was used to identify effective factors (group, age, gender, tooth type). Significance was set at (p \< 0.05). Keywords: Apical periodontitis, SWEEPS, Ultrasonic activation, Cytokines, MMP-9, Endodontics.

Gender: MALE

Ages: 18 Years - 35 Years

Updated: 2026-04-01

1 state

Apical Periodontitis
Retreatment
Biomarkers
+1
RECRUITING

NCT07012759

Pleural Effusion Biomarkers in Lung Adenocarcinoma Patients

This project aims to assess the expression levels of novel molecular markers identified through screening in clinical samples of malignant pleural effusion, to evaluate the feasibility and clinical utility of these markers as potential diagnostic genes for lung adenocarcinoma.

Gender: All

Ages: 18 Years - Any

Updated: 2026-03-05

Biomarkers
Lung Adenocarcinoma
Pleural Effusion
ACTIVE NOT RECRUITING

NCT04793360

Molecular Assessment and Profiling of Liver Transplant Recipients

The objective of this protocol is to conduct longitudinal and prospective studies of liver transplant recipients, using a multimodality approach, akin to that used in kidney transplantation. The primary aim will compare the clinical outcomes of LiverCare post-transplant surveillance in liver transplant with standard of care consisting of liver function tests, DSA measurements, drug level monitoring, and 'for cause' biopsy. The protocol will assess the correlation between clinical events (e.g. rejection, recurrent disease, biliary obstruction), dd-cfDNA levels, gene expression profiling, ability to assess microchimerism, develop predictive analytics, infectious disease diagnoses and finally examine graft histology.

Gender: All

Ages: 12 Years - Any

Updated: 2026-02-23

21 states

Liver Transplantation
Biomarkers
RECRUITING

NCT03268668

Thrombus Composition in Ischemic Stroke: Analysis of the Correlation With Plasma Biomarkers, Efficacy of Treatment, Etiology and Prognosis

The recent validation of thrombectomy in addition to thrombolysis with intravenous administration of alteplase suggests a major revolution in the management of acute strokes. This treatment option also opens up a new field of research, making possible the analysis of the clot responsible for intracranial occlusion. Indeed, in about 30% of the cases, the thrombectomy procedure makes it possible to retrieve either partially or completely the clot. Previous studies have analyzed the correlation between the composition of the thrombus and the etiology of stroke. Their discordant results do not yet make it possible to distinguish a particular profile of thrombus according to etiology. Other studies have shown a correlation between the proportion of red blood cells in a thrombus and the likelihood that it is visible in MRI or cerebral scanning. More recently, one study has demonstrated a correlation between the presence of lymphocytes in the thrombus and an atheromatous etiology. The main limitations of these studies are the small number of patients included, the high variability of conservation protocols and the absence of plasma data, which does not allow for research on the correlation between clot composition and plasma biomarkers.

Gender: All

Ages: 18 Years - Any

Updated: 2026-01-20

Stroke, Acute
Biological Specimen Banks
Biomarkers
+2
RECRUITING

NCT07071649

Evaluation of a Plasma Marker (p-Tau217) for the Biological Diagnosis of Alzheimer's Disease, and Comparison With CSF Markers

The biological diagnosis of AD is actually performed by analysing Aβ1-40 and Aβ1-42 peptides, total tau and tau phosphorylated at Thr181 (p-Tau181) from cerebrospinal fluid (CSF) samples obtained by lumbar puncture (LP). Phospho-Tau 217 (p-Tau217) is a new biomarker that could be measured in plasma. The aim of this study is to compare the performances of plasma p-Tau217 with those of the reference CSF biomarkers in 150 patients recruited in the memory center of CHU Amiens (France). The study will be conducted during 18 months. The inclusion will be proposed to all patients for whom an indication of lumbar puncture / CSF is raised in a context of clinical suspicion of AD. During the daily hospitalization during which CSF will be collected for the "classical" biomarkers testing, a single tube of blood will be collected (anticoagulant EDTA, collected for p-Tau 217 analysis). The performances of CSF and plasma pTau 217 will be compared with the clinical diagnosis of AD (+, -, or indeterminate).

Gender: All

Ages: 18 Years - Any

Updated: 2026-01-16

Alzheimer's Disease
Biomarkers
Non-invasive Diagnosis
+1
RECRUITING

NCT07345286

Clinical Aspects, Management and Surveillance of Febrile Illnesses in DRC

The epidemiology and outcome of febrile illnesses in the Democratic Republic of Congo (DRC) is poorly documented. The FIKI² study, a prospective observational study of community-acquired febrile illnesses coordinated by ITM and INRB and conducted at 2 clinical sites from 2021 to 2023, has deepened the knowledge of clinical presentation, etiology, outcome and profile of inflammatory/infectious biomarkers (white blood cells and C-reactive protein, or CRP). The management of febrile illnesses remains fraught with clinical challenges. Overuse of antibiotics in primary care remains a reality in the field, and has been observed in several studies, including FIKI². A number of initiatives are underway to address this problem, such as the use of biomarkers, the development of treatment guidelines and electronic decision support systems. The FIKI² study highlighted the potential role of CRP in rationalizing antibiotic use. In parallel, the 'AWARE antibiotic book' was published at the end of 2022 by the WHO, providing recommendations on the choice (or otherwise) of antibiotic therapy for over 30 common clinical infections, in both primary care and hospital settings. Based on the results of the FIKI² study, the main aim of the FI-CARE study is to investigate the impact of these new tools (CRP biomarker, AWARE antibiotic book, and electronic decision support systems) on first-line antibiotic use. Secondly, the study will consolidate previous results from FIKI² sites in terms of monitoring the etiologies of community-acquired febrile illnesses (particularly arboviruses); and reinforce this monitoring at new sites (depending on opportunities). This complementary study will also pursue FIKI²'s strategic objectives of strengthening clinical research capacity and consolidating biobanks in the DRC. FI-CARE is a prospective, observational, multicenter cohort study of adults and children presenting to the emergency department or outpatient clinic with community-acquired febrile illness. A laboratory component with sample storage in a biobank is added in a modular fashion according to laboratory and research capacities, epidemiological interest and available funds.

Gender: All

Ages: 2 Months - Any

Updated: 2026-01-15

Febrile Illness Acute
Biomarkers
Surveillance
NOT YET RECRUITING

NCT06938191

Comparison of Aquaporin -4, -5, -9 and IL-8 Levels in GCF, Dentin Fluid and Pulp Samples

This study aimed to compare the changes in AQP -4, -5, -9, and IL-8 levels in pulp tissue, GCF, and dentin fluid samples routinely obtained during the treatment of healthy and symptomatic teeth diagnosed with irreversible pulpitis and investigate whether there is a correlation between them. A total of 70 patients aged 18-64 years with healthy (Group 1) and symptomatic irreversible pulpitis (Group 2) diagnosed at Kırıkkale University, Faculty of Dentistry, Department of Endodontics who will undergo routine root canal treatment will be included in the study, with a minimum of 35 participants for each group. Before starting treatment, DOS samples will be taken from healthy, symptomatic, irreversible pulpitis-diagnosed teeth and teeth contralateral to these teeth. A dentin fluid sample will be taken by holding the membrane on the dentin surface, and the pulp tissue will be removed and transferred to Eppendorf tubes. The treatment process will be completed by applying routine root canal procedures to the teeth. The samples' Aquaporin -4, -5, -9, and IL-8 levels will be analyzed by specific enzyme-linked immunosorbent assay (ELISA).

Gender: All

Ages: 18 Years - 64 Years

Updated: 2025-12-01

Pulpitis
Pulpitis - Irreversible
Pulp Inflammation
+2
RECRUITING

NCT06276335

Influence of Timing of Implant Placement on Early Healing Molecular Events

Dental implants have been on the market for several years and they are routinely used to replace single/multiple missing teeth with a high success rate. However, there is still a limited number of studies comparing the influence of timing of implant placement on wound healing. In addition, there is no data available on the signaling pathways and the expression of healing biomarkers involved in the early stages of osseointegration after immediate implant placement (IP) or delayed implant placement (DP). The primary objective of this study is to describe changes in the expression of inflammatory, angiogenesis and osseous biomarkers of saliva at 1, 3, 7, 15 and 30 days and of PICF at 3, 7, 15 and 30 days after immediate implant placement (IP) compared with delayed placement (DP).

Gender: All

Ages: 25 Years - Any

Updated: 2025-11-19

Dental Implant
Healing Wound
Biomarkers
+1
RECRUITING

NCT05988658

Combining Biomarkers and Electronic Risk Scores to Predict AKI in Hospitalized Patients

The study's objective is to evaluate the additive value of renal biomarkers (from blood and urine) for identifying individuals at high risk for severe acute kidney injury (AKI) above that of a novel natural language processing (NLP)-based AKI risk algorithm. The risk algorithm is based on electronic health records (EHR) data (labs, vitals, clinical notes, and test reports). Patients will enroll at the University of Chicago Medical Center and the University of Wisconsin Hospital, where the risk score will run in real time. The risk score will identify those patients with the highest risk for the future development of Stage 2 AKI and collect blood and urine for biomarker measurement over the subsequent 3 days.

Gender: All

Ages: 18 Years - Any

Updated: 2025-09-12

2 states

Acute Kidney Injury
Biomarkers
RECRUITING

NCT07171151

Detection of Disease Marker Factors in Cyst Fluid

The purpose of this observational study is to examine the cyst fluid obtained after a puncture procedure performed for cyst diagnosis in participants with cystic lesions on clinical and radiological examination.The main question it aims to answer is: \- What is the exact mechanism of formation of odontogenic cysts? Biomarkers in the cyst fluid obtained after a puncture procedure performed as part of the diagnosis and treatment process of odontogenic cysts will be examined. The aim of this study is to gain insight into cyst pathology by examining the levels of biomarkers in odontogenic cyst fluid.

Gender: All

Ages: 12 Years - 80 Years

Updated: 2025-09-12

Biomarkers
NOT YET RECRUITING

NCT07130448

The Relation of Albumin/Globulin Ratio and Platelet/Albumin Ratio to Lupus Nephritis

Albumin/globulin ratio and platelet/albumin ratio as a predictive non-invasive biomarker for lupus nephritis (LN) presence and severity

Gender: All

Ages: 18 Years - Any

Updated: 2025-08-19

Lupus Nephritis (LN)
SLE - Systemic Lupus Erythematosus
Biomarkers
RECRUITING

NCT05372159

Vanderbilt Memory and Aging Project

This study will use an observational cohort to cross-sectionally and longitudinally relate vascular health to clinical, imaging, and biological markers of early Alzheimer's disease and cerebrovascular disease among aging adults. Adjusting for relevant clinical covariates, we will test the hypothesis that vascular health is associated with clinical, brain magnetic resonance imaging (MRI), neuropsychological, and cerebrospinal fluid markers of early cerebrovascular and Alzheimer's disease changes (i.e., prior to the onset of significant cognitive decline or dementia). Secondarily, we will examine medical and genetic factors that might mediate associations between vascular health and brain aging, such as inflammatory processes, insulin resistance, and genetic factors (e.g., APOE, a susceptibility risk factor for dementia). Findings will advance knowledge regarding the role that vascular health plays in brain aging.

Gender: All

Ages: 60 Years - Any

Updated: 2025-08-06

1 state

Alzheimer Disease
Aging
Aged, 80 and Over
+5
NOT YET RECRUITING

NCT07101029

Effect of Bio-C Temp Versus Calcium Ydroxide as Intracanal Dressings on Postoperative Pain Intensity and Periapical MMP-9 Level in Patients With Necrotic Pulp

To compare the effect of Bio-C Temp Bioceramic intracanal dressing versus calcium hydroxide as intracanal medicaments on: * Intensity of postoperative pain * levels of MMP -9 in Periapical Fluids.

Gender: All

Ages: 18 Years - 50 Years

Updated: 2025-08-03

Intracanal Dressing
Apical Periodontitis
Calcium Hydroxide
+2
NOT YET RECRUITING

NCT07092969

Comparison of the Effects of Aerobic-Anaerobic Exercises on Hormonal and Immune Biomarkers

This study aims to compare the effects of aerobic and anaerobic exercise on hormonal, immunological, and metabolic biomarkers in young individuals using blood and saliva samples. It will also assess participants' physical activity levels, depression levels, and general lifestyle habits to explore their relationship with biomarker profiles. Biomarkers such as testosterone, progesterone, cortisol, IgA, alpha-amylase, insulin, lactate, and various inflammatory cytokines will be measured using ELISA. The study seeks to evaluate the physiological and psychosocial effects of different types of exercise in a holistic manner.

Gender: All

Ages: 18 Years - 25 Years

Updated: 2025-07-30

Activity, Motor
Biomarkers
Exercise
+1