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ClinicalTrials.gov is a database of privately and publicly funded clinical studies conducted around the world.

Explore 495,057 research studies in all 50 states and in 222 countries..

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Clinical Trials Information for Patients and Caregivers

Explore the basics of clinical trials, including what they are, how they work, and what to expect. Learning all you can about clinical trials can help you talk with your doctor and decide what is right for you.

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Find an NCI-supported clinical trial—and learn how to locate other research studies—that may be right for you or a loved one.

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Learn about the possible risks and benefits of joining a clinical trial and questions to ask about trials.

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Clinical Trials

Clinical trials are research studies that involve people and test new ways to prevent, detect, diagnose, or treat diseases. Many medical procedures and treatments used today are the result of past clinical trials.

Taking part in a clinical trial has potential benefits and risks. The potential benefits of participating in a trial include the following:

• Trial participants have access to promising new procedures or treatments that are generally not available outside of a clinical trial.
• The new procedure or treatment being studied may be more effective than the current usual approach. If it is more effective, trial participants may be the first to benefit from it.
• Trial participants receive high-quality medical care from a research team that includes doctors, nurses, and other health professionals.
• The results of the trial may help other people who need medical care in the future.
• Trial participants are helping scientists learn more about cancer and other medical conditions, which will lead to more advances.

Some of the potential risks of taking part in a clinical trial are:

• The new procedure or drug may not be better than what is currently available, or it may have side effects that doctors do not expect or that are worse than the side effects of the current usual approach.
• Trial participants may be required to make more visits to the doctor than they would if they were not in a clinical trial and/or need to travel farther for those visits.
• Some of the costs of participating in a trial may not be covered by health insurance.

The decision to take part in a clinical trial is a personal one. Your health care team and your loved ones, if you wish, can assist you in deciding whether or not a clinical trial is right for you. The final decision, however, is yours alone to make.

Visit ClinicalTrials.gov to search for NIH-sponsored colorectal cancer clinical trials that are currently accepting patients.

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• example: diabetes
• result: finds clinical studies containing the word diabetes
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The 10 Most Significant Education Studies of 2021

From reframing our notion of “good” schools to mining the magic of expert teachers, here’s a curated list of must-read research from 2021.

It was a year of unprecedented hardship for teachers and school leaders. We pored through hundreds of studies to see if we could follow the trail of exactly what happened: The research revealed a complex portrait of a grueling year during which persistent issues of burnout and mental and physical health impacted millions of educators. Meanwhile, many of the old debates continued: Does paper beat digital? Is project-based learning as effective as direct instruction? How do you define what a “good” school is?

Other studies grabbed our attention, and in a few cases, made headlines. Researchers from the University of Chicago and Columbia University turned artificial intelligence loose on some 1,130 award-winning children’s books in search of invisible patterns of bias. (Spoiler alert: They found some.) Another study revealed why many parents are reluctant to support social and emotional learning in schools—and provided hints about how educators can flip the script.

1. What Parents Fear About SEL (and How to Change Their Minds)

When researchers at the Fordham Institute asked parents to rank phrases associated with social and emotional learning , nothing seemed to add up. The term “social-emotional learning” was very unpopular; parents wanted to steer their kids clear of it. But when the researchers added a simple clause, forming a new phrase—”social-emotional & academic learning”—the program shot all the way up to No. 2 in the rankings.

What gives?

Parents were picking up subtle cues in the list of SEL-related terms that irked or worried them, the researchers suggest. Phrases like “soft skills” and “growth mindset” felt “nebulous” and devoid of academic content. For some, the language felt suspiciously like “code for liberal indoctrination.”

But the study suggests that parents might need the simplest of reassurances to break through the political noise. Removing the jargon, focusing on productive phrases like “life skills,” and relentlessly connecting SEL to academic progress puts parents at ease—and seems to save social and emotional learning in the process.

2. The Secret Management Techniques of Expert Teachers

In the hands of experienced teachers, classroom management can seem almost invisible: Subtle techniques are quietly at work behind the scenes, with students falling into orderly routines and engaging in rigorous academic tasks almost as if by magic. 

That’s no accident, according to new research . While outbursts are inevitable in school settings, expert teachers seed their classrooms with proactive, relationship-building strategies that often prevent misbehavior before it erupts. They also approach discipline more holistically than their less-experienced counterparts, consistently reframing misbehavior in the broader context of how lessons can be more engaging, or how clearly they communicate expectations.

Focusing on the underlying dynamics of classroom behavior—and not on surface-level disruptions—means that expert teachers often look the other way at all the right times, too. Rather than rise to the bait of a minor breach in etiquette, a common mistake of new teachers, they tend to play the long game, asking questions about the origins of misbehavior, deftly navigating the terrain between discipline and student autonomy, and opting to confront misconduct privately when possible.

3. The Surprising Power of Pretesting

Asking students to take a practice test before they’ve even encountered the material may seem like a waste of time—after all, they’d just be guessing.

But new research concludes that the approach, called pretesting, is actually more effective than other typical study strategies. Surprisingly, pretesting even beat out taking practice tests after learning the material, a proven strategy endorsed by cognitive scientists and educators alike. In the study, students who took a practice test before learning the material outperformed their peers who studied more traditionally by 49 percent on a follow-up test, while outperforming students who took practice tests after studying the material by 27 percent.

The researchers hypothesize that the “generation of errors” was a key to the strategy’s success, spurring student curiosity and priming them to “search for the correct answers” when they finally explored the new material—and adding grist to a 2018 study that found that making educated guesses helped students connect background knowledge to new material.

Learning is more durable when students do the hard work of correcting misconceptions, the research suggests, reminding us yet again that being wrong is an important milestone on the road to being right.

4. Confronting an Old Myth About Immigrant Students

Immigrant students are sometimes portrayed as a costly expense to the education system, but new research is systematically dismantling that myth.

In a 2021 study , researchers analyzed over 1.3 million academic and birth records for students in Florida communities, and concluded that the presence of immigrant students actually has “a positive effect on the academic achievement of U.S.-born students,” raising test scores as the size of the immigrant school population increases. The benefits were especially powerful for low-income students.

While immigrants initially “face challenges in assimilation that may require additional school resources,” the researchers concluded, hard work and resilience may allow them to excel and thus “positively affect exposed U.S.-born students’ attitudes and behavior.” But according to teacher Larry Ferlazzo, the improvements might stem from the fact that having English language learners in classes improves pedagogy , pushing teachers to consider “issues like prior knowledge, scaffolding, and maximizing accessibility.”

5. A Fuller Picture of What a ‘Good’ School Is

It’s time to rethink our definition of what a “good school” is, researchers assert in a study published in late 2020.⁣ That’s because typical measures of school quality like test scores often provide an incomplete and misleading picture, the researchers found.

The study looked at over 150,000 ninth-grade students who attended Chicago public schools and concluded that emphasizing the social and emotional dimensions of learning—relationship-building, a sense of belonging, and resilience, for example—improves high school graduation and college matriculation rates for both high- and low-income students, beating out schools that focus primarily on improving test scores.⁣

“Schools that promote socio-emotional development actually have a really big positive impact on kids,” said lead researcher C. Kirabo Jackson in an interview with Edutopia . “And these impacts are particularly large for vulnerable student populations who don’t tend to do very well in the education system.”

The findings reinforce the importance of a holistic approach to measuring student progress, and are a reminder that schools—and teachers—can influence students in ways that are difficult to measure, and may only materialize well into the future.⁣

6. Teaching Is Learning

One of the best ways to learn a concept is to teach it to someone else. But do you actually have to step into the shoes of a teacher, or does the mere expectation of teaching do the trick?

In a 2021 study , researchers split students into two groups and gave them each a science passage about the Doppler effect—a phenomenon associated with sound and light waves that explains the gradual change in tone and pitch as a car races off into the distance, for example. One group studied the text as preparation for a test; the other was told that they’d be teaching the material to another student.

The researchers never carried out the second half of the activity—students read the passages but never taught the lesson. All of the participants were then tested on their factual recall of the Doppler effect, and their ability to draw deeper conclusions from the reading.

The upshot? Students who prepared to teach outperformed their counterparts in both duration and depth of learning, scoring 9 percent higher on factual recall a week after the lessons concluded, and 24 percent higher on their ability to make inferences. The research suggests that asking students to prepare to teach something—or encouraging them to think “could I teach this to someone else?”—can significantly alter their learning trajectories.

7. A Disturbing Strain of Bias in Kids’ Books

Some of the most popular and well-regarded children’s books—Caldecott and Newbery honorees among them—persistently depict Black, Asian, and Hispanic characters with lighter skin, according to new research .

Using artificial intelligence, researchers combed through 1,130 children’s books written in the last century, comparing two sets of diverse children’s books—one a collection of popular books that garnered major literary awards, the other favored by identity-based awards. The software analyzed data on skin tone, race, age, and gender.

Among the findings: While more characters with darker skin color begin to appear over time, the most popular books—those most frequently checked out of libraries and lining classroom bookshelves—continue to depict people of color in lighter skin tones. More insidiously, when adult characters are “moral or upstanding,” their skin color tends to appear lighter, the study’s lead author, Anjali Aduki,  told The 74 , with some books converting “Martin Luther King Jr.’s chocolate complexion to a light brown or beige.” Female characters, meanwhile, are often seen but not heard.

Cultural representations are a reflection of our values, the researchers conclude: “Inequality in representation, therefore, constitutes an explicit statement of inequality of value.”

8. The Never-Ending ‘Paper Versus Digital’ War

The argument goes like this: Digital screens turn reading into a cold and impersonal task; they’re good for information foraging, and not much more. “Real” books, meanwhile, have a heft and “tactility”  that make them intimate, enchanting—and irreplaceable.

But researchers have often found weak or equivocal evidence for the superiority of reading on paper. While a recent study concluded that paper books yielded better comprehension than e-books when many of the digital tools had been removed, the effect sizes were small. A 2021 meta-analysis further muddies the water: When digital and paper books are “mostly similar,” kids comprehend the print version more readily—but when enhancements like motion and sound “target the story content,” e-books generally have the edge.

Nostalgia is a force that every new technology must eventually confront. There’s plenty of evidence that writing with pen and paper encodes learning more deeply than typing. But new digital book formats come preloaded with powerful tools that allow readers to annotate, look up words, answer embedded questions, and share their thinking with other readers.

We may not be ready to admit it, but these are precisely the kinds of activities that drive deeper engagement, enhance comprehension, and leave us with a lasting memory of what we’ve read. The future of e-reading, despite the naysayers, remains promising.

9. New Research Makes a Powerful Case for PBL

Many classrooms today still look like they did 100 years ago, when students were preparing for factory jobs. But the world’s moved on: Modern careers demand a more sophisticated set of skills—collaboration, advanced problem-solving, and creativity, for example—and those can be difficult to teach in classrooms that rarely give students the time and space to develop those competencies.

Project-based learning (PBL) would seem like an ideal solution. But critics say PBL places too much responsibility on novice learners, ignoring the evidence about the effectiveness of direct instruction and ultimately undermining subject fluency. Advocates counter that student-centered learning and direct instruction can and should coexist in classrooms.

Now two new large-scale studies —encompassing over 6,000 students in 114 diverse schools across the nation—provide evidence that a well-structured, project-based approach boosts learning for a wide range of students.

In the studies, which were funded by Lucas Education Research, a sister division of Edutopia , elementary and high school students engaged in challenging projects that had them designing water systems for local farms, or creating toys using simple household objects to learn about gravity, friction, and force. Subsequent testing revealed notable learning gains—well above those experienced by students in traditional classrooms—and those gains seemed to raise all boats, persisting across socioeconomic class, race, and reading levels.

10. Tracking a Tumultuous Year for Teachers

The Covid-19 pandemic cast a long shadow over the lives of educators in 2021, according to a year’s worth of research.

The average teacher’s workload suddenly “spiked last spring,” wrote the Center for Reinventing Public Education in its January 2021 report, and then—in defiance of the laws of motion—simply never let up. By the fall, a RAND study recorded an astonishing shift in work habits: 24 percent of teachers reported that they were working 56 hours or more per week, compared to 5 percent pre-pandemic.

The vaccine was the promised land, but when it arrived nothing seemed to change. In an April 2021 survey  conducted four months after the first vaccine was administered in New York City, 92 percent of teachers said their jobs were more stressful than prior to the pandemic, up from 81 percent in an earlier survey.

It wasn’t just the length of the work days; a close look at the research reveals that the school system’s failure to adjust expectations was ruinous. It seemed to start with the obligations of hybrid teaching, which surfaced in Edutopia ’s coverage of overseas school reopenings. In June 2020, well before many U.S. schools reopened, we reported that hybrid teaching was an emerging problem internationally, and warned that if the “model is to work well for any period of time,” schools must “recognize and seek to reduce the workload for teachers.” Almost eight months later, a 2021 RAND study identified hybrid teaching as a primary source of teacher stress in the U.S., easily outpacing factors like the health of a high-risk loved one.

New and ever-increasing demands for tech solutions put teachers on a knife’s edge. In several important 2021 studies, researchers concluded that teachers were being pushed to adopt new technology without the “resources and equipment necessary for its correct didactic use.” Consequently, they were spending more than 20 hours a week adapting lessons for online use, and experiencing an unprecedented erosion of the boundaries between their work and home lives, leading to an unsustainable “always on” mentality. When it seemed like nothing more could be piled on—when all of the lights were blinking red—the federal government restarted standardized testing .

Change will be hard; many of the pathologies that exist in the system now predate the pandemic. But creating strict school policies that separate work from rest, eliminating the adoption of new tech tools without proper supports, distributing surveys regularly to gauge teacher well-being, and above all listening to educators to identify and confront emerging problems might be a good place to start, if the research can be believed.

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In brief: what types of studies are there.

Last Update: September 8, 2016 ; Next update: 2024.

There are various types of scientific studies such as experiments and comparative analyses, observational studies, surveys, or interviews. The choice of study type will mainly depend on the research question being asked.

When making decisions, patients and doctors need reliable answers to a number of questions. Depending on the medical condition and patient's personal situation, the following questions may be asked:

• What is the cause of the condition?
• What is the natural course of the disease if left untreated?
• What will change because of the treatment?
• How many other people have the same condition?
• How do other people cope with it?

Each of these questions can best be answered by a different type of study.

In order to get reliable results, a study has to be carefully planned right from the start. One thing that is especially important to consider is which type of study is best suited to the research question. A study protocol should be written and complete documentation of the study's process should also be done. This is vital in order for other scientists to be able to reproduce and check the results afterwards.

The main types of studies are randomized controlled trials (RCTs), cohort studies, case-control studies and qualitative studies.

• Randomized controlled trials

If you want to know how effective a treatment or diagnostic test is, randomized trials provide the most reliable answers. Because the effect of the treatment is often compared with "no treatment" (or a different treatment), they can also show what happens if you opt to not have the treatment or diagnostic test.

When planning this type of study, a research question is stipulated first. This involves deciding what exactly should be tested and in what group of people. In order to be able to reliably assess how effective the treatment is, the following things also need to be determined before the study is started:

• How long the study should last
• How many participants are needed
• How the effect of the treatment should be measured

For instance, a medication used to treat menopause symptoms needs to be tested on a different group of people than a flu medicine. And a study on treatment for a stuffy nose may be much shorter than a study on a drug taken to prevent strokes .

“Randomized” means divided into groups by chance. In RCTs participants are randomly assigned to one of two or more groups. Then one group receives the new drug A, for example, while the other group receives the conventional drug B or a placebo (dummy drug). Things like the appearance and taste of the drug and the placebo should be as similar as possible. Ideally, the assignment to the various groups is done "double blinded," meaning that neither the participants nor their doctors know who is in which group.

The assignment to groups has to be random in order to make sure that only the effects of the medications are compared, and no other factors influence the results. If doctors decided themselves which patients should receive which treatment, they might – for instance – give the more promising drug to patients who have better chances of recovery. This would distort the results. Random allocation ensures that differences between the results of the two groups at the end of the study are actually due to the treatment and not something else.

Randomized controlled trials provide the best results when trying to find out if there is a cause-and-effect relationship. RCTs can answer questions such as these:

• Is the new drug A better than the standard treatment for medical condition X?
• Does regular physical activity speed up recovery after a slipped disk when compared to passive waiting?
• Cohort studies

A cohort is a group of people who are observed frequently over a period of many years – for instance, to determine how often a certain disease occurs. In a cohort study, two (or more) groups that are exposed to different things are compared with each other: For example, one group might smoke while the other doesn't. Or one group may be exposed to a hazardous substance at work, while the comparison group isn't. The researchers then observe how the health of the people in both groups develops over the course of several years, whether they become ill, and how many of them pass away. Cohort studies often include people who are healthy at the start of the study. Cohort studies can have a prospective (forward-looking) design or a retrospective (backward-looking) design. In a prospective study, the result that the researchers are interested in (such as a specific illness) has not yet occurred by the time the study starts. But the outcomes that they want to measure and other possible influential factors can be precisely defined beforehand. In a retrospective study, the result (the illness) has already occurred before the study starts, and the researchers look at the patient's history to find risk factors.

Cohort studies are especially useful if you want to find out how common a medical condition is and which factors increase the risk of developing it. They can answer questions such as:

• How does high blood pressure affect heart health?
• Does smoking increase your risk of lung cancer?

For example, one famous long-term cohort study observed a group of 40,000 British doctors, many of whom smoked. It tracked how many doctors died over the years, and what they died of. The study showed that smoking caused a lot of deaths, and that people who smoked more were more likely to get ill and die.

• Case-control studies

Case-control studies compare people who have a certain medical condition with people who do not have the medical condition, but who are otherwise as similar as possible, for example in terms of their sex and age. Then the two groups are interviewed, or their medical files are analyzed, to find anything that might be risk factors for the disease. So case-control studies are generally retrospective.

Case-control studies are one way to gain knowledge about rare diseases. They are also not as expensive or time-consuming as RCTs or cohort studies. But it is often difficult to tell which people are the most similar to each other and should therefore be compared with each other. Because the researchers usually ask about past events, they are dependent on the participants’ memories. But the people they interview might no longer remember whether they were, for instance, exposed to certain risk factors in the past.

Still, case-control studies can help to investigate the causes of a specific disease, and answer questions like these:

• Do HPV infections increase the risk of cervical cancer ?
• Is the risk of sudden infant death syndrome (“cot death”) increased by parents smoking at home?

Cohort studies and case-control studies are types of "observational studies."

• Cross-sectional studies

Many people will be familiar with this kind of study. The classic type of cross-sectional study is the survey: A representative group of people – usually a random sample – are interviewed or examined in order to find out their opinions or facts. Because this data is collected only once, cross-sectional studies are relatively quick and inexpensive. They can provide information on things like the prevalence of a particular disease (how common it is). But they can't tell us anything about the cause of a disease or what the best treatment might be.

Cross-sectional studies can answer questions such as these:

• How tall are German men and women at age 20?
• How many people have cancer screening?
• Qualitative studies

This type of study helps us understand, for instance, what it is like for people to live with a certain disease. Unlike other kinds of research, qualitative research does not rely on numbers and data. Instead, it is based on information collected by talking to people who have a particular medical condition and people close to them. Written documents and observations are used too. The information that is obtained is then analyzed and interpreted using a number of methods.

Qualitative studies can answer questions such as these:

• How do women experience a Cesarean section?
• What aspects of treatment are especially important to men who have prostate cancer ?
• How reliable are the different types of studies?

Each type of study has its advantages and disadvantages. It is always important to find out the following: Did the researchers select a study type that will actually allow them to find the answers they are looking for? You can’t use a survey to find out what is causing a particular disease, for instance.

It is really only possible to draw reliable conclusions about cause and effect by using randomized controlled trials. Other types of studies usually only allow us to establish correlations (relationships where it isn’t clear whether one thing is causing the other). For instance, data from a cohort study may show that people who eat more red meat develop bowel cancer more often than people who don't. This might suggest that eating red meat can increase your risk of getting bowel cancer. But people who eat a lot of red meat might also smoke more, drink more alcohol, or tend to be overweight. The influence of these and other possible risk factors can only be determined by comparing two equal-sized groups made up of randomly assigned participants.

That is why randomized controlled trials are usually the only suitable way to find out how effective a treatment is. Systematic reviews, which summarize multiple RCTs , are even better. In order to be good-quality, though, all studies and systematic reviews need to be designed properly and eliminate as many potential sources of error as possible.

• German Network for Evidence-based Medicine. Glossar: Qualitative Forschung.  Berlin: DNEbM; 2011. 
• Greenhalgh T. Einführung in die Evidence-based Medicine: kritische Beurteilung klinischer Studien als Basis einer rationalen Medizin. Bern: Huber; 2003. 
• Institute for Quality and Efficiency in Health Care (IQWiG, Germany). General methods . Version 5.0. Cologne: IQWiG; 2017.
• Klug SJ, Bender R, Blettner M, Lange S. Wichtige epidemiologische Studientypen. Dtsch Med Wochenschr 2007; 132:e45-e47. [ PubMed : 17530597 ]
• Schäfer T. Kritische Bewertung von Studien zur Ätiologie. In: Kunz R, Ollenschläger G, Raspe H, Jonitz G, Donner-Banzhoff N (eds.). Lehrbuch evidenzbasierte Medizin in Klinik und Praxis. Cologne: Deutscher Ärzte-Verlag; 2007.

IQWiG health information is written with the aim of helping people understand the advantages and disadvantages of the main treatment options and health care services.

Because IQWiG is a German institute, some of the information provided here is specific to the German health care system. The suitability of any of the described options in an individual case can be determined by talking to a doctor. informedhealth.org can provide support for talks with doctors and other medical professionals, but cannot replace them. We do not offer individual consultations.

Our information is based on the results of good-quality studies. It is written by a team of health care professionals, scientists and editors, and reviewed by external experts. You can find a detailed description of how our health information is produced and updated in our methods.

• Cite this Page InformedHealth.org [Internet]. Cologne, Germany: Institute for Quality and Efficiency in Health Care (IQWiG); 2006-. In brief: What types of studies are there? [Updated 2016 Sep 8].

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'Surprisingly' high number of adults in the U.S. at risk of heart syndrome

Nearly 90% of adults over age 20 in the United States are at risk of developing heart disease , an alarming new study suggests. 

While the unexpectedly high number doesn't mean that the majority of adults in the U.S. have full-blown heart disease, it does indicate that many are at risk of developing the condition, even younger people.

Researchers identified people at high risk using a recently defined syndrome that takes into account the strong links between heart disease, obesity, diabetes and kidney disease, according to the research published Wednesday in JAMA.

The American Heart Association alerted doctors in October about cardiovascular-kidney-metabolic (CKM) syndrome , a condition which affects major organs in the body, including the brain, heart, liver and kidneys. CKM is diagnosed in stages ranging from zero — no risk factors for heart disease — to 4 — people with diagnosed heart disease plus excess body fat, metabolic risk factors such as hypertension and diabetes, or kidney disease.

For the new study, researchers analyzed almost a decade’s worth of data from more than 10,000 people who were participating in the National Health and Nutrition Examination Survey (NHANES).

“We absolutely were surprised that almost 90% of people met the criteria,” said study co-author Dr. Rahul Aggarwal, a cardiology fellow at Brigham and Women’s Hospital, Harvard Medical School, in Boston. “It was much higher than we anticipated in a database that included younger adults.”

Especially concerning was the finding that almost 50% of the NHANES participants were at stage 2 of CKM, meaning that they were at moderate risk because they had either high blood sugar, hypertension, high cholesterol or chronic kidney disease, Aggarwal said.

Just more than a quarter of the group — people listed as stage 1 — were at increased risk of developing heart disease because of being obese or overweight, having excess belly fat and fat around their organs, but didn't have specific symptoms.

The researchers found that 15% of the participants had advanced disease, a number that remained fairly constant between 2011 and 2020.  

“I think one of the biggest factors contributing to the fact that the percentage of people in advanced stages is not improving is obesity, which is very prevalent in the U.S.,” Aggarwal said, adding that 40% of people in America are obese. Another 32% are overweight based on body mass index calculations , according to the Centers for Disease Control and Prevention. 

Carrying excess pounds increases the likelihood a person will have high blood pressure, high blood sugar and high cholesterol, although some have metabolic risk factors even if they are at a healthy weight.

 Participants older than 65 were more likely to be at an advanced stage than people between 45 to 64. But being young wasn’t as protective as one might assume. Only 18% of people ages 20 through 44 were at stage zero. That is, they had no risk factors.  

The new findings show that health care providers need to be picking up on these conditions earlier “before they lead to downstream effects,” such as increased risk of heart attack, heart failure and stroke, Aggarwal said. “We need to diagnose earlier and be more aggressive at treating people.”

Latest news on heart health

• Science shows how a surge of anger could raise heart attack risk.
• Intermittent fasting linked to a higher risk of cardiovascular death, new analysis finds.
• High levels of a common B vitamin linked to heart disease.

Adopting lifestyle changes, such as improved diets and increased activity, can help protect against heart attack and stroke.The findings also show that “young adults, those younger than 45, are not as healthy as we thought they were,” Aggarwal said. 

Experts were also surprised by the high rates of CKM. 

“It is alarming that 90% of the population is at least stage 1 and only 10% have no risk factors,” said Dr. Sripal Bangalore, a professor of medicine and director of invasive and interventional cardiology at NYU Langone Health in New York City. 

He blames the epidemic of overweight and obesity for those numbers. 

“We have a lot of work to do to reduce the rates of overweight and obesity,” Bangalore said. “If we can do that, then hopefully we can reduce the number of people who progress to stage 2 and also move the needle down for higher stages.”

The inclusion of kidney disease in the risk assessments for cardiovascular disease makes a lot of sense, said Dr. Adriana Hung, a kidney specialist and epidemiologist and a professor of medicine at the Vanderbilt University Medical Center in Nashville, Tennessee. 

“Kidney disease magnifies cardiovascular disease,” she said. “Some studies show that a patient has as much as six times the risk of dying from cardiovascular disease if kidney disease is also present.”

The new, broader approach to heart disease is likely to help identify more people who are at risk, said Dr. Robert Rosenson, director of lipids and metabolism for the Mount Sinai Health System in New York City. 

“The main message from this study should be that many common behaviors are leading to an accumulation of diseases over one’s lifetime, which will impact quality of life and survival,” he said. 

The large numbers of people with CKM in this study are related to overweight and obesity, insulin resistance and a diet that is high in fat and salt, Rosenson added. 

People need to realize that it’s not just the heart that is being harmed by unhealthy diets and lack of exercise, he said, but that lifestyle factors also have an effect on cognition.

Linda Carroll is a regular health contributor to NBC News. She is coauthor of "The Concussion Crisis: Anatomy of a Silent Epidemic" and "Out of the Clouds: The Unlikely Horseman and the Unwanted Colt Who Conquered the Sport of Kings." 

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• 07 May 2024

US funders to tighten oversight of controversial ‘gain of function’ research

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A US policy that goes into effect next year tightens oversight of risky pathogen research conducted in biosafety facilities. Credit: Associated Press/Alamy Stock Photo

After years of deliberation, US officials have released a policy that outlines how federal funding agencies and research institutions must review and oversee biological experiments on pathogens with the potential to be misused or spark a pandemic.

The policy, which applies to all research funded by US agencies and will take effect in May 2025, broadens oversight of these experiments. It singles out work involving high-risk pathogens for special oversight and streamlines existing policies and guidelines, adding clarity that researchers have been seeking for years.

“This is a very welcome development,” says Jaime Yassif, vice-president of global biological policy and programmes at the Nuclear Threat Initiative, a research centre in Washington DC that focuses on national-security issues. “The US is the biggest funder of life sciences research [globally], so we have a moral obligation to guard against risks.”

Balancing act

Manipulating pathogens such as viruses inside an enclosed laboratory facility, sometimes by making them more transmissible or harmful (called gain-of-function research), can help scientists to assess their risk to society and develop countermeasures such as vaccines or antiviral drugs. But the worry is that such pathogens could accidentally escape the laboratory or even become weaponized by people with malicious intent.

Policymakers have had difficulty developing a clearly articulated review system that evaluates the risks and benefits of this research, while ensuring that fundamental science needed to prepare for the next pandemic and to advance medicine isn’t paralysed. The latest policy, released on 6 May by the US Office of Science and Technology Policy, is the next stage of a long-running US balancing act between totally banning high-risk pathogen research and assessing it with standards that some say are too ambiguous.

The shifting sands of ‘gain-of-function’ research

In 2014, after several accidents involving mishandled pathogens at US government laboratories, the presidential administration announced a moratorium on funding for research that could make certain pathogens — such as influenza and coronaviruses — more dangerous, given their potential to unleash an epidemic or pandemic. At the time, some researchers said the ban threatened necessary flu surveillance and vaccine research.

The government ended the moratorium in 2017, after the US National Science Advisory Board for Biosecurity (NSABB), a panel of experts that advises the US government, concluded that very few experiments posed a risk. That year, the US Department of Health and Human Services (HHS) instead implemented a review framework for proposals from scientists seeking federal funding for experiments involving potential pandemic pathogens. This framework applied to proposals to any agency housed under the HHS, including the National Institutes of Health (NIH) — the largest public funder of biomedical research in the world.

Researchers raised concerns about the transparency of this review process, and the NSABB was asked to revisit these policies and guidelines in 2020, but the COVID-19 pandemic delayed any action until 2022. During that time, the emergence of the coronavirus SARS-CoV-2 , and the ensuing debate over whether it had leaked from a lab in China, put biosafety at the top of researchers’ minds worldwide. The NIH, in particular, was scrutinized during the pandemic for its role in funding potentially risky coronavirus research. In response, some Republican lawmakers have — so far unsuccessfully — put forward legislation that would once again place a moratorium on research that might increase the transmissibility or virulence of pathogens.

Finding a balance

The latest policy aims to address concerns that have arisen over the past decade about lax oversight, ambiguous wording and lack of transparency.

It breaks potentially problematic research into two categories. The first includes research on biological pathogens or toxins that could generate knowledge, technologies or products that could be misused. The second includes research on pathogens with enhanced pandemic potential.

Research falls into the first category if it meets several criteria. For example, it must involve high-risk biological agents, such as smallpox, that are on specific lists. It must also have particular experimental outcomes, such as increasing an agent’s deadliness.

Research that falls into the second category includes pathogens intended to be modified in a way that is “reasonably anticipated” to make them more dangerous. That criterion means that even research on pathogens that are not typically considered dangerous — seasonal influenza, for example — can fall into the second category. Previously, pathogen surveillance and vaccine-development research were not subject to additional oversight in the United States; the latest policy eliminates this exception, but clarifies that both surveillance and vaccine research are “typically not within the scope” of research in the second category.

Layers of review

Scientists and their institutions are responsible for identifying research that falls into the two categories, the policy states. Once the funding agency confirms that a research proposal fits into either group, that agency will request a risk–benefit assessment and a risk-mitigation plan from the investigator and institution. If a proposal is deemed to fit into the second category, it will undergo an extra review before the project gets the green light. A report of all federally funded research that fits into the second category will be made public every year.

NIH reinstates grant for controversial coronavirus research

The directive also mandates that agencies outside the HHS that fund biological research, such as the US Department of Defense, must abide by the same rules. This is a huge step forward, says Tom Inglesby, director of the Johns Hopkins Center for Health Security in Baltimore, Maryland. But it applies only to federally funded research; the policy recommends, but does not require, that non-governmental organizations and the private sector follow the same rules.

Federal agencies and research institutions will now create their own implementation plans to comply with the policy before it goes into effect in 2025. Yassif says that the policy’s success will hinge on how these stakeholders implement it.

Nevertheless, the policy sets a worldwide standard and might inspire other countries to re-evaluate how they oversee life-sciences research, says Filippa Lentzos, a biosecurity researcher at King’s College London who chairs an advisory group for the World Health Organization (WHO) on the responsible use of life-sciences research. Later this month, at the World Health Assembly in Geneva, Switzerland, WHO member states will consider a proposal to urge nations to cooperate on developing international standards for biosecurity.

Nature 629 , 510-511 (2024)

doi: https://doi.org/10.1038/d41586-024-01377-x

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