Clinical trials
Observational Study clinical trials
Below are recruiting observational study clinical trials, each written for real people, not researchers. We’re tracking 839 recruiting studies, each written for real people, not researchers, below.
Recruiting studies
- NCT06897007Recruiting
Ciprofol dosage in patients with insomnia under anesthesia
This study looks at how the sedative drug ciprofol works differently in people with insomnia compared to those who sleep well. It aims to help doctors give the right dose for your type of surgery.
Beijing, Beijing MunicipalityAges 18–64 - NCT07028190Recruiting
Rimazolen dose in insomnia patients under anesthesia
This trial looks at how much Rimazolen, a sleep medicine, is needed during surgery for people with insomnia compared to normal sleepers. It aims to find the right dose for better recovery.
Beijing, Beijing MunicipalityAges 18–64 - NCT04291612Recruiting
Observational study of standard surgery for uterine cancer in women
This is a research study that looks at outcomes in women with endometrial (uterine) cancer who receive the usual standard surgery. Researchers will group patients based on the final surgical and pathology results and what additional (if any) treatment is recommended afterward.
Hartford, ConnecticutAges 18 years+ - NCT07716969Recruiting
Reducing time without treatment for psychosis
This trial tests a program to help people get treatment faster for psychosis. It is for patients who have started OPUS treatment within the last 9 months and may have a schizophrenia-related condition.
Copenhagen, DenmarkAges 18–35 - NCT07154823Recruiting
Blood cancer registry study for biomarker discovery
This study collects samples and health information from people with certain blood cancers to learn more about the disease and find markers that may help guide future treatments. You will not receive a treatment from this study, but you may help advance research.
Iowa City, IowaAges birth+ - NCT07368465Recruiting
What affects weight gain in late pregnancy?
This study looks at how your physical activity, eating habits, and anxiety levels may affect how much weight you gain during pregnancy. It aims to find ways to support healthy weight gain for you and your baby.
IstanbulAges 18–45 - NCT07543419Recruiting
Real-world Study of Secukinumab for Moderate to Severe Hidradenitis Suppurativa
This study tracks how secukinumab (a new medication) works for hidradenitis suppurativa—a painful skin condition with recurring boils and abscesses—in real-world patient care in Italy. Researchers want to understand treatment patterns and outcomes to help improve care for this condition.
Ancona, ANAges 18–100 - NCT07069400Recruiting
Observational study of adults with acute infection
This study observes adults hospitalized with a new or recent infection (symptoms started within 30 days). The goal is to learn more about how infections affect people in the hospital, without testing any new drugs or treatments.
Tucson, ArizonaAges 18 years+ - NCT04330599Recruiting
COVID-19 study following people in the UK
This observational study follows how COVID-19 affects people in the UK over time. It may help researchers understand patterns of illness and health changes, without testing a new treatment.
London, County (optional)Ages 16 years+ - NCT07347002Enrolling by invitation
Observational study of chikungunya vaccine effectiveness in Brazil
This study looks at how well the VLA1553 vaccine prevents chikungunya disease in parts of Brazil where the vaccine is being offered as part of a pilot program. If you live in one of those areas and have had symptoms that might be chikungunya, this study will use your health records and blood tests to check how effective the vaccine is.
Belo Horizonte, Minas GeraisAges 18–59 - NCT07707622Enrolling by invitation
Sepsis treatment study for ICU patients
This trial studies treatments for sepsis, a serious infection complication, in ICU patients. It aims to find better ways to care for critically ill patients with sepsis.
BeijingAges 18 years+ - NCT03151473Recruiting
Study of adults with fatty liver and NASH over time
This is a long-term study that follows adults who are being managed for fatty liver (NAFL) or NASH to learn how these conditions change over time. It may help researchers better understand what to expect and how care decisions could be improved.
Hong KongAges 18 years+ - NCT03409263Recruiting
Registry for people with TIPS for high portal pressure
This study is a registry, meaning it collects health information to better understand people who have a TIPS procedure for high pressure in the liver’s blood vessels. It may help doctors improve how TIPS is used and monitored over time.
Vienna, State of ViennaAges 18–99 - NCT03605771Recruiting
Observes people with advanced melanoma in Spain since 2018
This observational study collects information about people with advanced (stage III/IV) melanoma, including cases that are metastatic or cannot be removed by surgery. It may help improve understanding of how melanoma behaves and how it’s being treated across Spain.
Alcoy, AlicanteAges 18 years+ - NCT03620786Recruiting
HIFU experience study for treating parts of the prostate
This observational study looks at outcomes after people choose HIFU (high-intensity focused ultrasound) to treat only a targeted area of the prostate. It may help doctors better understand how well HIFU works and what follow-up imaging or testing shows over time.
Los Angeles, CaliforniaAges 40–85 - NCT03809585Recruiting
Study of iris tumors and healthy eyes
This observational study looks at eyes with iris tumors and compares them to eyes without iris problems. The goal is to better understand how iris circulation and related eye measurements differ, which may help future care.
Portland, OregonAges 18 years+ - NCT04111692Recruiting
Watching foam treatment for cysts in autosomal polycystic disease
This study follows adults with inherited kidney and/or liver cysts that are causing symptoms to see how a foam sclerotherapy procedure may help and what outcomes happen over about a year. You may be eligible if you have a few sizable, specific-type cysts and can safely attend follow-up visits.
Rochester, MinnesotaAges 18–100 - NCT04151342Recruiting
Study of Canadian adults with cancer rare DNA changes
This real-world study follows adults in Canada who have cancer that was tested and found to have rare molecular (DNA/protein) changes. It helps researchers understand how these rare findings show up and how care happens in everyday practice.
Calgary, AlbertaAges 18 years+ - NCT04179370Recruiting
Vitamin D and health in British African-Caribbean women
This study looks at vitamin D levels and how they relate to overall health in British African-Caribbean women. It may help researchers understand whether vitamin D support or lifestyle changes could benefit this group.
GuildfordAges 18 years+ - NCT04181970Recruiting
Study of sarcoma care quality across Europe and Latin America
This observational study looks at information from people with sarcoma to understand how care is delivered across different centers. It does not test a new treatment, but may help improve future care and planning.
Buenos AiresAges 18–120 - NCT04252066Recruiting
Pregnancy and breastfeeding study for women with Fabry disease
This study follows pregnant and breastfeeding women with Fabry disease (and their infants) to better understand what happens during pregnancy and early life. You may or may not be taking migalastat, and the goal is to gather real-world information that could help future care.
Philadelphia, PennsylvaniaAges Any age - NCT04318366Recruiting
Study of COVID-19 samples and how patients respond to treatment
This trial collects and studies COVID-19 test results and other patient information to better predict treatment response and outcomes. Your sample(s) help researchers understand who may improve, worsen, or need different care.
Milan, LombardyAges 18 years+ - NCT04504006Recruiting
Tracking surgery choices for lymph node spread in endometrial cancer
This is an observational study that follows people with endometrial cancer who have had surgery to check and remove pelvic (and sometimes paraaortic) lymph nodes. It looks at how different surgical approaches and any added treatment affect local control (keeping cancer from coming back in the pelvis/nearby areas).
Essen, North Rhine-WestphaliaAges 18 years+ - NCT04561518Recruiting
Study of people with TTR amyloidosis worldwide
This is an observational study (no study drug) for people with transthyretin (TTR)–mediated amyloidosis, including people who carry certain gene changes before symptoms begin. It may help researchers better understand how the disease affects health over time and what to measure in future treatments.
La Jolla, CaliforniaAges Any age
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 839 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.