Clinical trials
Observational Study clinical trials
Below are recruiting observational study clinical trials, each written for real people, not researchers. We’re tracking 818 recruiting studies, each written for real people, not researchers, below.
Recruiting studies
- NCT05960370Recruiting
Testing a tighter embryo placement technique in natural frozen transfers
This study looks at whether “endometrial compaction” (a technique used during frozen embryo transfer) improves pregnancy and baby outcomes. It focuses on people having a frozen transfer using embryos that test normal on genetic screening.
MadridAges 18–50 - NCT05562323Recruiting
Study of immune response after monkeypox vaccination
This is an observational study that follows adults after they get a monkeypox vaccine to learn how their immune system responds. The results may help researchers understand what types of protection the vaccine creates.
Badalona, BarcelonaAges 18 years+ - NCT05812248Recruiting
Tracking heart and blood vessel events after major non-heart surgery
This study follows people after major surgery to see what predicts heart and blood vessel problems later. It does not test a new drug; it mainly collects health information to help clinicians reduce risk.
Guangzhou, GuangdongAges 45 years+ - NCT05784038Recruiting
Study of monkeypox infection in Brazil
This is an observational study that follows people with confirmed monkeypox (mpox) to better understand the illness over time. It may help doctors learn what to expect and improve care, but it does not test a new treatment.
Belém, ParáAges 18 years+ - NCT04113447Recruiting
Mitochondrial donation study for parents of confirmed mtDNA mutation
This study follows families using mitochondrial donation to reduce the risk from a confirmed mitochondrial DNA (mtDNA) mutation. It aims to learn outcomes over about 18 months of the child’s life and whether the treatment works well and safely for families like yours.
Newcastle upon Tyne, Tyne & WearAges Any age - NCT02784977Recruiting
Sleep apnea study using a national sleep database
This study collects information from adults who are getting a sleep test because obstructive sleep apnea is suspected. It helps researchers better understand sleep apnea and who develops it, without giving a new treatment.
IstanbulAges 18–80 - NCT07800754Recruiting
Stomach and esophageal cancer care in Greece
This study is for people with stomach or esophageal cancer in Greece. It is not a treatment study; it simply looks at how patients are diagnosed and treated in regular practice, so participating won't change your care.
AlexandroupoliAges 18–130 - NCT07655583RecruitingPhase 1
Skipping radiation after brain surgery
This study is for people with melanoma or lung cancer that has spread to the brain and who have had surgery to remove the brain tumor. It looks at whether it is safe to skip the usual radiation treatment after surgery, while taking a targeted drug therapy that is known to be effective in the brain.
Houston, TexasAges 18 years+ - NCT07702357Enrolling by invitation
Preschool outcomes study for ReDiMOM children
This study follows up on children who were part of the ReDiMOM study to see how they are doing in preschool. It helps researchers understand the long-term effects of the earlier study.
Chicago, IllinoisAges 2–6 - NCT07561489Enrolling by invitation
Study of OsteoPearl Implants for Spine Fractures
This study observes how a biological implant called OsteoPearl helps people recover from recent spine fractures in the mid or lower back. Researchers will track your pain relief and ability to function over time after a minimally invasive procedure to stabilize the fracture.
Williamsville, New YorkAges 50 years+ - NCT03199066Recruiting
Study of non-Hodgkin lymphoma patients in the Czech Republic
This is an observational study that collects real-world information from people diagnosed with non-Hodgkin lymphoma. It does not test a new drug, but it may help doctors understand patient outcomes and care patterns.
PragueAges 18 years+ - NCT03418961RecruitingPhase 3
Study of heart-risk management for metastatic HER2 breast cancer
This trial follows people with metastatic HER2-positive breast cancer who are at higher risk for heart damage while on HER2-targeted therapy. Some participants are randomly assigned to different monitoring/heart-protection approaches to see what best helps keep the heart safe.
Anchorage, AlaskaAges 18 years+ - NCT07421895Recruiting
Study on retained tissue after pregnancy
This study follows patients with retained products of conception (tissue left in the uterus after a pregnancy) to see how they are managed in real-world medical practice. You may join if an ultrasound shows a tissue area of at least half a centimeter.
Changsha, HunanAges 18–45 - NCT07399808Recruiting
CDK4/6 Inhibitors in Older Breast Cancer Patients
This study looks at how well CDK4/6 inhibitors work in older adults with breast cancer who are taking these drugs after surgery to help prevent the cancer from coming back. It will follow patients over time to learn more about their experiences.
Pavia, PaviaAges 18 years+ - NCT07388628Recruiting
Observing ARTICE® treatment in the ICU
This study is collecting real-world data on ARTICE® treatment for adults in the ICU. It helps doctors understand how this treatment works in daily practice.
MagdeburgAges 18 years+ - NCT07359183Recruiting
Long-term follow-up of kids who had oral immunotherapy for allergies
This study checks on children and young people 5 to 15 years after they finished an 18-month oral immunotherapy treatment for peanut, egg, or milk allergy. It helps researchers understand how their allergies and health are doing over the long term.
Parkville, VictoriaAges Any age - NCT07546682Recruiting
Propel Sinus Implant Study in Japan
This study tests a steroid-releasing implant placed during sinus surgery to help prevent inflammation and improve healing in patients with chronic sinus infections. If you're having sinus surgery in Japan, this trial may track how well the implant works for you.
AsahikawaAges 18 years+ - NCT06577779RecruitingPhase 4
Testing Jornay PM for adult ADHD symptoms into the evening
This study tests if Jornay PM, a long-acting ADHD medication, helps control symptoms, focus, and emotions throughout the day and into the early evening in adults with ADHD. It is an open-label study, meaning everyone knows they are getting the medication, and then they are randomly assigned to different observation groups.
New York, New YorkAges 18–60 - NCT07211321Recruiting
Diet, inflammation, and muscle loss in older adults
This study looks at how diet and gut health relate to muscle loss (sarcopenia) in adults 60 and older. It aims to understand links between inflammation, gut bacteria, and muscle strength so we can find better ways to prevent frailty.
Lanzhou, GansuAges 60 years+ - NCT07001267Recruiting
Comparing two anesthetics for stroke procedure recovery
This trial tests whether a sedative given through an IV or a gas you breathe affects recovery after surgery to remove a blood clot in the brain. It may help find the best way to keep you comfortable during the procedure to improve how well you do after three months.
Kansas City, KansasAges 18 years+ - NCT06926244Recruiting
Studying resistance to IgA nephropathy treatments in real life
This study observes how people with IgA nephropathy respond to standard and newer treatments in everyday medical practice, to understand why some cases are resistant to therapy.
ParisAges 18 years+ - NCT06889844Recruiting
Blood test for colorectal cancer cross-reactivity study
This research study uses a blood test to look for signs of colorectal cancer in people who have other types of cancer or digestive diseases. The goal is to see if the test can correctly tell the difference between colorectal cancer and other conditions.
Málaga, AndalusiaAges 18 years+ - NCT06822634Recruiting
Advanced imaging for rectal cancer treatment response
This trial uses advanced MRI scans to see how well rectal cancer is responding to radiotherapy. It may help doctors better understand which treatments work best for patients with more advanced disease.
GlasgowAges 18 years+ - NCT06764602Recruiting
Kidney health in kids with tuberous sclerosis
This study looks back at medical records to see how many children with tuberous sclerosis complex (TSC) have kidney problems. It may help doctors understand how common kidney issues are in kids with TSC.
BolognaAges Up to 17 years
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Common questions
- Are there clinical trials for observational study?
- Yes. Clin2 currently lists 818 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.