Clinical trials
Observational Study clinical trials
Below are recruiting observational study clinical trials, each written for real people, not researchers. We’re tracking 836 recruiting studies, each written for real people, not researchers, below.
Recruiting studies
- NCT07657520Recruiting
High-Altitude Brain Health Study
This study follows healthy Han Chinese adults living at high altitudes to see how the brain changes over time. It may help learn why some people develop Parkinson's disease or other movement problems.
Chengdu, SichuanAges 40–75 - NCT07111364Recruiting
Ultrasound with AI to diagnose bladder tumors
This study uses ultrasound with AI to better diagnose bladder masses. It's for people who have a suspicious finding on a bladder ultrasound and are already planning to have surgery to treat it.
BeijingAges 18–85 - NCT07270861Recruiting
Study of peripheral T-cell lymphoma outcomes in real-world care
This study is looking at how peripheral T-cell lymphoma (PTCL) behaves and responds to treatment in real-world settings. It includes patients diagnosed over many years to better understand the disease and improve care.
Shanghai, Shanghai MunicipalityAges 18 years+ - NCT06001138Enrolling by invitation
FutureMS-2: A Follow-Up Study for MS
This study follows up with people who have Multiple Sclerosis and were in the earlier FutureMS study. It uses MRI scans to learn more about MS and find better ways to treat it.
AberdeenAges 18 years+ - NCT07184892Recruiting
Swallowing therapy after stroke
This study tests if watching swallowing movements (action observation therapy) helps people recover swallowing function after a first-time stroke. It uses a brain imaging technique called fNIRS to see how the brain responds.
Jinan, ShandongAges 18–80 - NCT05939414RecruitingPhase 3
Lutetium prostate cancer treatment for limited PSMA-spread
This Phase 3 trial compares a targeted radiation medicine called lutetium (177Lu) vipivotide tetraxetan versus watchful waiting in people with prostate cancer that has spread to only a few spots. The goal is to see if the treatment can better control the cancer when scans show a small amount of PSMA-positive metastases.
Fayetteville, ArkansasAges 18–100 - NCT07413211Recruiting
Natural history study for genetic epilepsy and developmental delays
This study follows children and adults with genetic conditions that cause severe epilepsy and developmental delays (DEE), including those with MEF2C mutations. It aims to better understand these disorders and prepare for future clinical trials. You or your child can join in person (travel to NYC), virtually (online), or by filling out a registry.
New York, New YorkAges Any age - NCT07167433Recruiting
Observational study of ovarian cancer from 2021 onward
This study looks at the real-world experiences of patients with ovarian cancer, whether newly diagnosed or with persistent or recurrent disease. It aims to learn more about the disease and its treatment over time.
Barretos/SPAges 18 years+ - NCT05236114Recruiting
Study of blood and tumor tests for lung cancer treatment
This study looks at how tumor and blood biomarker results can guide treatment for people with non-small cell lung cancer (NSCLC). Depending on the cancer stage, it may follow standard-of-care treatment plans around surgery or first-line immunotherapy.
Birmingham, AlabamaAges 18 years+ - NCT06021769Recruiting
Pessary experience study for pelvic support
This study follows women who get a pessary (a supportive device placed in the vagina) for pelvic organ prolapse or stress urinary incontinence. Researchers want to learn about their experiences with the fitting and use of the pessary.
Charlottesville, VirginiaAges 18 years+ - NCT06271213Recruiting
Gut-lung study for children with breathing problems
This study looks at how the gut and lungs affect breathing problems in children. It compares samples from children with and without respiratory illnesses to understand why some children get sicker than others.
GlasgowAges birth–16 years - NCT07711912Enrolling by invitation
Polish AntiReflux Study (POLAR)
This study looks at how well acid reflux surgery works for people with GERD (chronic heartburn). If you're already scheduled for this surgery at a participating hospital, you may be able to join.
Olsztyn, Warminsko-mazusrkieAges 18 years+ - NCT07729891Recruiting
Vital sign monitoring after urological surgery
This study tests a system that constantly watches your vital signs (like heart rate and blood pressure) after urological surgery, to catch problems early. It's for people who are not expected to need the Intensive Care Unit after their operation.
Parma, ParmaAges 18 years+ - NCT03245866Recruiting
Study for bleeding caused by a brain aneurysm rupture
This study is for people admitted with a confirmed brain bleeding caused by a ruptured aneurysm. The goal is to better understand this specific cause of bleeding, which may help improve care for patients with aneurysm-related subarachnoid hemorrhage.
Aarau, Canton of AargauAges Any age - NCT04772170Recruiting
Study wearable and symptom monitoring during respiratory virus challenges
This observational study looks for digital health patterns during studies where people are intentionally exposed to a respiratory virus. If you join a respiratory virus challenge at NIH, you may help researchers discover better ways to monitor and understand illness using wearable devices and shared health data.
Bethesda, MarylandAges 18–65 - NCT05890612Recruiting
Study of Paxlovid safety and effectiveness in high-risk COVID-19
This study observes people at higher risk for severe COVID-19 who take Paxlovid, to better understand how well it works and how safe it is in real-world use. It may help doctors confirm the best way to use Paxlovid and spot any side effects.
SeoulAges 19 years+ - NCT07512609Recruiting
How Environment and Inflammation Affect Metabolic Health
This study explores how environmental factors and inflammation in your body might contribute to metabolic diseases like diabetes and heart disease. Researchers will analyze health data from people who've had physical exams to find patterns that could help prevent or manage these conditions.
ChongqingAges Any age - NCT06773884Enrolling by invitation
Hip fracture surgery study using nationwide data
This study looks at the records of adults who had hip fracture surgery. It might help explain how different treatments affect recovery and health results.
ÖrebroAges 18 years+ - NCT04428489Enrolling by invitation
Follow-up for low blood counts without MDS
This study follows people with ongoing low blood counts (red cells, white cells, and/or platelets) to better understand their condition when it does not meet criteria for MDS. It may help improve how persistent blood count problems are evaluated over time.
Suzhou, JiangsuAges 18 years+ - NCT05397717Recruiting
Study of outcomes after spontaneous collapsed lung
This study follows adults with a “spontaneous pneumothorax,” meaning a lung collapse that happens without trauma, to see what outcomes they experience. You may be followed during and after hospitalization, because your results can help doctors understand and improve care.
Hong KongAges 18 years+ - NCT06706206Recruiting
Heart artery care in hemophilia study
This study uses a special CT scan to check for heart artery disease in men with hemophilia. It aims to better understand heart risks in this group.
Oxford, OxfordshireAges 45–120 - NCT06897670Recruiting
Brain blood flow patterns in mood and memory disorders
This study uses a headband with light sensors (fNIRS) to measure blood flow in the brain while you do thinking tasks. It aims to understand differences in brain activity for people with depression, bipolar disorder, or mild memory loss.
Rochester, MinnesotaAges 18 years+ - NCT07081841Enrolling by invitation
Long-term follow-up for AB-1005 study participants
This trial is for people with Parkinson's disease or multiple system atrophy (parkinsonian type) who took part in an earlier AB-1005 study. It will continue to monitor your health over time to learn more about the treatment's long-term effects.
San Francisco, CaliforniaAges Any age - NCT05234177Recruiting
Blood test to track colorectal cancer after surgery
This study looks at a blood “DNA” test to see if it can help monitor colorectal cancer after surgery. It may benefit you by improving how doctors track cancer during routine follow-up visits.
Fort Smith, ArkansasAges 18 years+
Hear when a new Observational Study trial opens
We’ll email you when one opens — at most once a week, no account needed, unsubscribe anytime.
Common questions
- Are there clinical trials for observational study?
- Yes. Clin2 currently lists 836 recruiting observational study studies from the U.S. registry, each rewritten for real people, not researchers, so you can see what it’s testing and who it’s for.
- How do I know if I qualify for a observational study trial?
- Each study lists its eligibility criteria — rules about age, diagnosis, and prior treatments. On every Clin2 trial page we explain these in words written for real people and offer a short, optional pre-screen for a fit read. The study team makes the final decision.
- Does it cost anything to join a observational study trial?
- Using Clin2 is always free. Many trials cover the cost of the study treatment and related visits; some reimburse travel. The study team explains exactly what’s covered before you decide.
Related conditions
Clin2 helps you find and understand clinical trials and does not provide medical advice. Study data comes from ClinicalTrials.gov. Talk with your doctor about whether a specific trial is right for you.