Clinical trials
Observational Study clinical trials
Below are recruiting observational study clinical trials, each written for real people, not researchers. We’re tracking 845 recruiting studies, each written for real people, not researchers, below.
Recruiting studies
- NCT05814237Recruiting
Study of new respiratory infections starting within 10 days
This is an observational study that follows adults who are newly sick with a respiratory infection that started within the past 10 days. It may help researchers understand what causes these infections and how patients do in emergency or hospital-care settings.
BrusselsAges 18 years+ - NCT05818332Recruiting
ClassIntra® tool to improve outcomes during surgery
This trial tests whether using an in-the-operating-room learning/documentation tool (ClassIntra®) can improve care and outcomes for patients during surgery. You may be invited if you’re having certain inpatient operations with anesthesia involvement.
NijmegenAges 18–110 - NCT05821894Recruiting
Imaging study of plaque in neck arteries before surgery
This study uses pictures (imaging) to learn more about plaque in the neck arteries in people who are being considered for carotid endarterectomy. The results may help doctors better understand artery plaque and improve care.
Malmö, Skåne CountyAges 18 years+ - NCT05826665Recruiting
Study of heart rhythm mapping during AF ablation
This is an observational study that looks at how a special heart mapping system may affect the procedure and outcomes for people having ablation for persistent atrial fibrillation (AF). It may help doctors better understand what works best and how procedures turn out.
Jonesboro, ArkansasAges 18–80 - NCT05855252Recruiting
Study on monitoring and outcomes after moderate to severe head injury
This observational study follows adults with moderate to severe traumatic brain injury to understand care and outcomes. It collects information from the first 48 hours in the ICU and may help improve how clinicians monitor and treat patients in the critical early period.
Kogarah, New South WalesAges 18 years+ - NCT05855889Recruiting
Study of care for babies with congenital CMV infection
This is an observational study that looks at how babies with congenital CMV infection are diagnosed and managed in real life. It may help doctors understand which care approaches are used and how they relate to outcomes over time.
LondonAges Up to 10 years - NCT05858528Recruiting
Study following adults with skin psoriasis over time
This observational study is looking at adults with skin psoriasis and collecting real-world information about their condition and experiences. It may help researchers better understand psoriasis and how it affects people, without giving a new treatment.
Oxford, OxfordshireAges 18 years+ - NCT05885698Recruiting
Study of care patterns in newly diagnosed lung cancer
This observational study follows adults with newly diagnosed non-small cell lung cancer to understand what treatments are used and how patients are doing. It may help doctors better understand how care decisions affect outcomes, and it does not require the study to give an experimental treatment.
Daphne, AlabamaAges 18 years+ - NCT05907681Recruiting
Study outcomes after precise targeted radiation for metastatic breast cancer
This study follows people with breast cancer that has spread to other parts of the body who receive a highly precise form of radiation (like IMRT, SBRT, or proton therapy). It aims to see how well this treatment strategy works and what outcomes patients experience.
SeoulAges 19–100 - NCT05918510Recruiting
Blood and tumor study for virus markers in throat cancer
This study looks at virus-related markers and tiny gene regulators (microRNAs) in tumor tissue from people with certain throat cancers caused by human papilloma virus (HPV). It’s observational, meaning it does not change your treatment, but results may help doctors better understand these cancers and how they behave.
RomeAges 18 years+ - NCT05919511Recruiting
Questionnaire study for people at risk after stem cell transplant
This observational study follows people who had a stem cell transplant a few months ago to better understand risk for chronic graft-versus-host disease. You won’t get a study treatment; instead, you’ll complete questionnaires over time, and the study team looks at your symptoms and experiences.
Birmingham, AlabamaAges 18 years+ - NCT05926284Recruiting
Study of precision testing to guide treatment in advanced cancer
This study looks at how “precision medicine” testing on your tumor (or planning to do it) can help guide possible targeted treatments for advanced cancer. It is observational, meaning researchers mainly watch and record what happens as testing results become available.
BerlinAges 18 years+ - NCT05943652Recruiting
Study of how functional overlay affects movement disorders
This study looks at movement disorders that are functional (not caused by damage to the nervous system) or non-functional, and how a “functional overlay” may change symptoms. It is observational, meaning it does not test a new treatment, but it may help researchers better understand these differences and improve care.
Graz, StyriaAges 18–18 - NCT05958901Recruiting
Study of pulmonary hypertension in everyday clinical care
This observational study is looking at people diagnosed with pulmonary hypertension to better understand how it behaves over time. You may help researchers by allowing repeated check-ins for years and sharing symptom and test information.
Guangzhou, GuangdongAges 20–70 - NCT05968417Recruiting
Study of new lab tests using blood or bone marrow samples for myeloma
This trial studies myeloma (and closely related blood disorders) by using extra blood or bone marrow samples for lab research. It aims to help discover new ways to understand or treat myeloma.
SuttonAges 18 years+ - NCT05984576Recruiting
Chemo and radiation for recurrent rectal cancer after prior pelvic radiation
This study looks at combining total neoadjuvant therapy (chemotherapy and radiation) for rectal cancer that has come back in the pelvis after earlier radiation. It aims to see if this treatment approach can help control the disease and improve outcomes in patients with limited spread that can potentially be removed or treated.
RomeAges 18 years+ - NCT06017518Recruiting
Watching local relapse after high-grade osteosarcoma treatment
This study is watching people whose high-grade osteosarcoma came back in the same bone area (local relapse) after treatment. It helps doctors understand how local relapse happens, so they can improve future care.
Bologna, BOAges Any age - NCT06023030Recruiting
Observing how upadacitinib works for Crohn's disease in Japan
This study is for people with moderate to severe Crohn's disease who are starting a medication called upadacitinib. Researchers will watch how the disease changes over time and check for any side effects. It's an observational study, meaning you'll keep getting your regular treatment.
Anjo-shi, Aichi-kenAges 15 years+ - NCT06034509Recruiting
Thinking and blood vessel health after head injury
This study looks at how a past traumatic brain injury (TBI) might affect your thinking skills and blood vessel health over time. You may be eligible if you had a TBI at least 3 years ago and have already completed an earlier evaluation at the National Intrepid Center of Excellence (NICoE).
Bethesda, MarylandAges 18–74 - NCT06059963Recruiting
Simple blood test for colorectal cancer screening
This study is testing a new blood test (Signal-C) to see if it can help find colorectal cancer early. You may be able to join if you are average risk and getting a routine screening colonoscopy.
Raonoke, VirginiaAges 45–84 - NCT06067529Recruiting
Study on the health effects of early menopause
This study follows women with premature ovarian insufficiency (POI) over time to understand how it affects their health. Researchers will collect samples and track health changes to learn more about the condition and its long-term effects.
Hangzhou, ZhejiangAges 10–65 - NCT06069973Recruiting
Using AI to spot delayed brain injury after a brain bleed
This study uses artificial intelligence (machine learning) and blood tests to find early signs of delayed brain injury after a brain bleed. It aims to help doctors detect and treat this complication sooner.
GothenburgAges 18–110 - NCT06089980Recruiting
Kratom product study for regular users
This study watches how regular kratom users react to their own kratom product. It aims to learn more about kratom's effects in real-world settings.
Baltimore, MarylandAges 21 years+ - NCT06093022Recruiting
Treatment options for breast cancer that has spread to the liver
This study looks at how breast cancer that has spread to the liver responds to different treatments, including surgery and medicines. The goal is to learn which approach works best for patients with this condition.
Rome, LazioAges 18 years+
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Common questions
- Are there clinical trials for observational study?
- Yes. Clin2 currently lists 845 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.