Clinical trials & medical research (young people)

Different types of trials

Clinical trials cover a broad range of different types of research and are carried out in a number of stages - see our introductory explanation in ‘Why do we have clinical trials in children and young people?’ Here we focus on the different types of treatments and interventions which can be involved. 

Examples of how clinical trials can help:

Prevent illness by testing a vaccine

Detect or diagnose illnesses by testing a scan or blood test

Treat illness by testing a new medicine

Find out how best to provide psychological support

Find out how people can control symptoms or improve their quality of life by testing how a particular diet affects a condition

Preventive trials' look for better ways to prevent disease in people who have never had the disease or to prevent a disease from returning. These approaches may include medicines, vitamins, vaccines, minerals, or lifestyle changes.

Sophie, aged 23, explained why she wanted to take part in a research to help prevent the onset of diabetes in people with cystic fibrosis. Ruby and Joanna talked about taking part in trials to find the best treatment to help prevent thinning of bones in people who take steroids. 


Sophie took part in research to help stop people with cystic fibrosis developing diabetes. She says it is really important to detect changes in blood sugar levels early.

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Age at interview: 23
Sex: Female

So now that I’m a patient at [Hospital] and all my care is overseen by the specialist team there. One of the doctors asked if I would be interested in taking part in some research about blood sugar levels in people with cystic fibrosis. I’m in a position where hopefully I won’t develop diabetes because of the nature of my condition. I’m actually pancreatic sufficient but there is a chance that if I do become insufficient that I can develop diabetes. But in people with cystic fibrosis that are pancreatic insufficient, which is 90% of patients, the blood sugar levels can fluctuate and can lead to developing diabetes. And they’ve found that when a person’s having problems with the blood sugar levels, like when they’re too high or when they’re too low, it can affect their whole their health in general so it can affect their chest it can affect their lung function and it can affect their weight and it can affect many things. So it’s really important to be able to monitor blood sugar levels carefully and so people are receiving the right treatment. There is a test called the Oral Glucose Tolerance Test which is used commonly to, throughout the World, to diagnose diabetes. But this wasn’t developed with CF patients in mind it was developed in, for general diabetes, whereas CF related diabetes is slightly different. So, they’ve been looking at other ways of how to detect changes in blood sugar levels particularly in people with cystic fibrosis.

And something has been developed to help monitor blood sugar levels more carefully and it’s called a Continual Blood Glucose Monitor System. And the study which I took part in required me to wear this system it’s just like a little monitor for four days. So I was told briefly about it and I was given an information sheet explaining about the study which I read and I could ask any questions that I liked.


Ruby took part in a randomised placebo controlled trial on finding the best treatment to prevent...

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Age at interview: 17
Sex: Female
Age at diagnosis: 16
Well, I was diagnosed with lupus when I was 16, nearly 17. And then, from then I got asked, because I was put on steroid tablets, I was asked to, to do this POP study because steroids thin the bone, I think. And then the study is to see if any medicine could help to stop that happening. So I was asked to join that. And then from there…
It would be interesting to know who asked you and what information they gave you at that time?
The, a nurse came in to ask me, I think, and then she told me about the POP study, what it was about. So it was about like trying to un-, not thin the bones, stop, stop the steroids from thinning the bones. And then, yes…

Yes. They told me there was three drugs that they were testing and that I was going to be randomised to one of them. And then, from then I’d have to take that drug for a year. But I could stop if I wanted to.
So they give you an opportunity to withdraw?
So there were three drugs?
Yes, I think three.
Did they explain what the drugs were or, if they’d been trialed before?
They’d been trialing them for like five years, I think. And then, yes, they just explained that, what the different drugs were, but they didn’t exactly say properly what they were. But they were just like to try and help test the thinning of the bone.
Did they use a term like placebo at all?
Yes, they said one of them might be a placebo. But you’re not going to be told.

Did it bother you that you might have a placebo at all?
Not really, no.
Did you, if you were to explain what, what a placebo is, what did you understand about that?
It’s a drug but it’s not really a drug, so it doesn’t do anything. But it’s just to see if your mind makes, can change stuff.
And, but that, you, were you happy with that; were there any concerns about, you know, not knowing which drug?
Not really.
No. No, I’m fine really.
You were fine? And, and you, again what was the purpose of the actual trial itself?
To like try to stop the thinning of the bone from people who take steroids.



The trial will compare calcium with the trial drugs to see which one works. Joanna is hoping that...

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Age at interview: 17
Sex: Female
Age at diagnosis: 16
So what medication were you on before then, before the trial? You had the chemotherapy, but were you on, taking anything then?
Yes, I was, I’m still on now prednisolone, which is what they’re doing the trial for. Because it causes, because that’s the steroid and it causes brittle bones.
So you still take that?
Yes. I’m coming down off that now though.
And did they, do you understand what the purpose of the trial is, what they’re aiming to do?
Yes, to, like I said before, to like see if what I’m taking helps make my bones stronger. Or if it’s the calcium, because I get a tablet and I have to take calcium every night.
I was going to say, what, what is it? What does the trial involve for you? What do you have to do?
Yes, I have to take a tablet once a week and then calcium every night. Which is quite, it’s harder to remember taking it once a week instead of every day, because that’s just routine. But once a week is quite difficult to remember. And then the calcium to take every night. Because it’s not very nice to take them if you haven’t got juice in the house or something. It doesn’t taste nice.
Does it come as a liquid then?
No, it’s in a sachet and you’ve got to put it and mix it in your drink. And it’s not very nice to take either.
Isn’t it?
Do you have to take it with some juice?
Like take it with that?
And that’s every day?
Is that just once a day?
Yes, once a day.
And then, so you take that and then you have to take, what’s the, what do you have to take weekly?
It’s just, I was on a place-, I can’t say the word. The, you don’t know what it is. Because it could either be a false one or a real, real one, because they’re just trying to see, they’re try-, whether the calcium works best or the actual tablet works.
So were you randomised into –
Yes, groups, yes.
So tell me about that then, how that, how that goes about. What does that mean?
Some people have got the actual drug and some people have got the blank, what is it?
The placebo.
Yes, the pl-, yes. And you don’t know which one you’ve got. And you, we’ve all got to have the calcium as well. And whoever’s got the real drug, it’ll show whether that’s worked, compared to the people who’ve just been taking the calcium. And they compare it to see which is best, the calcium or the actual drug.


Both Will and Buddy took part in vaccine trials. Will took part in a swine flu vaccine trial and says “They were just seeing which one was the best on that they could use out on the public and stuff.” Buddy took part in a meningitis C vaccine trial and says' “It wasn’t really too bad. Because she came and talked to me about like what she was doing and it didn’t hurt. I had one vaccination and they took some blood”.

Drug trials' may be testing whether a new drug has any major side effects, or whether it works better than an existing treatment; but they may also test timing (when or how often to give a drug) or dosage (how much of the drug is needed to be effective). Drug trials are probably the most familiar type of trial to many people. Trials can also be used to test whether giving a treatment in a different way will make it more effective or reduce any side effects.

Lois is taking part in a randomised trial on improving the treatment for Grave’s disease, which usually affects women but is rare in teenage girls and even rarer in males. Grave’s disease means that Lois has an overactive thyroid gland and she has to take daily medication to help control it. 


Taking part in a trial made no difference to Lois, she was taking medication anyway. She is...

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Age at interview: 14
Sex: Female
Age at diagnosis: 13
So do you want to tell me about what the purpose of the trial is?
The purpose of the trial really was like there’s two medications thyroxine and carbimazole and it was like which, because there was like two medications for it but they weren’t sure which one was the better one and they wanted to find out which one would be like the better one really.
And if you think back to trying to remember how they might have explained that to you in the information or how it was explained to you?
Yes, they said that I, basically it said a lottery draw to decide which one, which medication you’re, you can have and I am like thyroxine and carbimazole.

Do you think it’s important that young people do take part in clinical trials?
Yes because you’ve got to understand that one day it could help like your children if they get it or it could help like a member of your family and stuff.
So it’s good to take part. And if you, in terms of your experience, I mean how has your experience been?
Liked it, it’s been like really good, I’ve never had no problems at all with it.



Lauren took part in a randomised trial on the side effects of a background insulin. She didn’t...

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Age at interview: 16
Sex: Female
Age at diagnosis: 13
The purpose of the trial is to see whether an illness, or the background insulin that you take when you’re on the carbohydrate regime is, makes you put on weight, has any side effects, if you lose weight or if it can, if it affects your, some part of your body. It’s just kind of that.
And just going back to that, because you mentioned also about not being tested, do you know whether it has been tested in young people before, this particular…?
I’ve no idea.
I know that beforehand mum was on like pig’s insulin. That was what they used before. And Novorapid and all the other insulin’s at the moment. But I don’t have a clue about any of that.
And what’s background insulin?
Background insulin is, when you’re on a carbohydrate regime, you take injections for the carbohydrates and the sugars you eat. And then because you don’t eat at night or during the night, you need a bit of insulin just to keep you, your sugar levels flat. Because you’ve obviously got the high, you’ve got your, say you have breakfast here, well, your sugars are going to shoot up, but then you take your injection and they’re going to go down again. But in the night they, they fluctuate and then the background insulin is just to keep them steady. And sometimes people have to take them in the night and some people just have to take them either in the morning or, but at night as well. Depending on what your sugars are like in the morning and what your sugars are like in the evening.
I used to be on Levemir, which is one type of background insulin, and Lantus is another. And in the trial you were to, you were randomised, and whatever category you were put in you either had to trial Lantus or Levemir. And you’d see how they affected your body or how you looked, or your diabetes and how they affected you. So everyone was put in to a computer and you were randomised, so they never set you out into certain groups.
And how did you feel about being randomised in to a group?
Well, I thought it was quite cool actually. I quite liked the idea because I have my own imagination, so I had this idea that all these names would appear on the screen and they’d all go in to like a big fuzzy thing and choose groups. But obviously that doesn’t happen. But I found that quite fun.
Do you know how they do randomise you?
No, I don’t.
It’s usually a computer.
Yes, I know it’s computerised because they told me. But I just had this lovely idea, so I… quite enjoyed it.
So you just got an idea in…
…your head and stuck with that? And what do, what if you were to explain to a young person what randomisation means, how would you describe it or explain it?
I would just describe it as kind of like pulling your name out of a hat and putting you randomly in to another hat or two hats. So say if everyone’s name was in a hat, and then you’d have two hats. And then you’d pick some, like five names out, but you didn’t know the names and you randomly put them in these two hats. And then you’d open the names at the end and whoever was in that hat would be for this and whoever was in the other hat would be for that. That’s my theory anyway.
That’s fine. And di

Alexander understands that the trial was to find out any side effects of the drug. He has...

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Age at interview: 18
Sex: Male
Age at diagnosis: 16
Each phase, you have to do this, of the trial. Each time, well, the first part is only over three months. So you have to sign to say, yes, you’re happy to do this. The second part is over six months. And this, the third part, this one I’m in is where you have to say, yes, I’m happy to go along with this long period of testing.
And do you understand the purpose of the trial?
I’m not 100 per cent sure. I think it’s to make sure the drug works, well, that’s kind of an obvious, and to make sure it works on a long-term basis. And to find out any long, long-term side effects or short-term, if there’s any damage. If it doesn’t do any damage, does it completely cure you or so on? That’s what I seem to have gathered from the doctors so far.
And in terms of the trial itself, what, can you, want to talk through that process, what’s involved? Because you talked about the first three months, then you talked about six months?
The beginning of the trial is just to put you on a drug. The first month, you have to go there three times, three visits to the hospital. The first is to get your first kind of check-up and your first injection of the medication. The second time is to get your second dose and a check-up. And then on the, sorry, that’s the first week and then the second week, and then on the fourth week you have your normal check-up and then you have your normal dose. And then they take you back on the second month. They only give you one dose on the second month. And then on the third month, the second dose. And that’s it.
That’s the first three, is that the first part?
Three months, yes, that’s the first section.
First three months? And is, what, is, when you talk about the, the drug, is that the trial drug?
That’s the trial medication, yes, sorry.
The second part, the second extension is for six months. And it’s, once again once every month you go back to the hospital and they give you a dose. But [now], this time it’s a randomised drug test. So it could be a placebo or you could be having the real thing. I think the, just to see if the drug actually works or if it’s in the mind or if it doesn’t do anything for you. It’s once again just a kind of experiment. But I only did that for about three to four months. And I was pretty sure I was on the placebo for the pure fact of my joints were getting worse and the kind of salmon-coloured rash was coming out again.
Is that the one that you had…?
Yes, that’s the arthritic rash.
That’s the arthritic, so it’s, that made itdid it make it worse or was it something new?
It was there before any of the medication, when I was on this medication. It does calm down but it sometimes still flares up. However this was, it flared up to how it used to be. It would cover my arms, legs, hands, anything. So that was kind of a, kind of an insurance, going, “Yes, maybe it’s not, you’re not on the drug any more, you’re on the placebo.” But how, because it was a double blind and I was no medical kind of worry, they didn’t take me off it. So, but after the third or fourth month they decided to call-up, because I was getting worse, but my bloods weren’t showing anything. And me and my mum went for lunch thinking, “Do I come off the drug? Do I stay on it?” So that was a good couple of hours, a littl

Graham is taking part in a clinical trial on the treatment of children and young people with Hodgkin’s lymphoma. Graham was unsure of the purpose of the trial but understood that it was to find out if treatment is just as successful by replacing one drug with another drug that is less likely to cause infertility or early menopause, and to find out what the long term effects are of each drug on fertility.


Taking part in the trial didn’t seem any different to the normal treatment says Graham.

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Age at interview: 16
Sex: Male
Age at diagnosis: 16
It’s pretty much the same as before I was in the clinical trial. Just, still have to go in to hospital for chemotherapy. Nothing’s really changed. Just a different treatment plan.
Just a different treatment plan? What’s, what’s, what’s different about it?
Just, for the first lot of treatment I had to go in on certain days for a short period of time, like an hour each day. But as it changed, I have to go in two days each treatment cycle for six hours each day. And that’s it. So it’s just changed times.
Just changed times? Is that okay?
Does it, do you have to keep, you know, going to and from the hospital to do that?
Yes, you have to go in on a certain day and just have chemotherapy.
And is that sort of weekly?
Yes, you have to start the treatment and then after a week, and then two weeks off and then start again.
So you have a week, a day?
A day at the start and then seven days, seven days at home on tablets. And then another, another day, and then another seven days on tablets. And then two weeks off, and then starting again. Yes, I take steroids and the procarbazine which is chemotherapy as well.
And is that done by drip?
I have, the chemo, yes, is done by a drip.
And how does it feel like going through all of, you know, being in a trial? What does it, what does it, does it feel any different?
No, not really. It doesn’t seem to feel any different than the normal treatment.



To take part in a Phase 2 trial that is at the forefront of medical science is really exciting...

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Sex: Male

Yes well the different trials are, have different purposes, so all the ones, so the one I did where I ended up on a placebo that was the double blind one to see, that’s were “Oh we know this drug is safe we just want to see if it has benefit”. Whereas the pilot study was specifically to see is the delivery of this drug safe, are there side effects how efficient does it seem to be and that. So that was on a smaller group of people and so from that point of view was reasonably, it was quite ground breaking actually and it was, it was exciting to take part in something that was virtually the forefront of medical science. Because it was using a different delivery for the gene therapy rather than a viral vector which most gene therapy uses it, it was it was using a different delivery mechanism which might mean it’s viable for multiple doses. 


Dr William van’t Hoff says ethics of research in children is being done with the purpose to...

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Nearly all medicines are tested in adults before they’re tried in children. And it is true of all such research that the safety of the people taking part in research is the most important standard that we are all holding to. And great care is undertaken to provide a plan of the research, called a protocol that puts safety first. And the governing principles around the clinical research are even stronger than those that relate to clinical care for instance in the NHS. That is, the standards of research practice have to be even safer and more stringent to protect the safety of participants, be they adult or child.

There are real concerns about undertaking research in children. A feeling that is perhaps unethical to do that. That children shouldn’t be experimented upon is the sort of thing one might hear or read about. And families and young people and children themselves and health professionals working with children are equally extremely sensitive that the research that is done has to be done under strict ethical guidance. And there are very clear ways, in which independent ethics committees and boards can check and supervise that the research practice is correct. I think there is an important statement to make about the ethics of research in children, and that is that it is being done with a purpose, and the purpose is to improve the treatment and improve the knowledge and the safety of medicines for children. And overall about half the medicines that are used in children have not had proper evidence and are being used in what is called off-label or in an unlicensed way compared to the proper license that has been granted for adult use. And there is an ethical dilemma between continuing a situation in which we have untested and unproven medications for children against the other side of the coin, as it were, in terms of testing these medicines in children in proper situations to improve the evidence base and give us a, a better, a better set of therapies for children.

Not all randomised trials are drug trials. They may also be testing other types of care, such as different levels of monitoring, the effect of different types of diet, or the effectiveness of different forms of screening e.g. 

Screening trials: detect or diagnose illnesses, for example, by using a scan or blood test.

Diagnostic trials: conducted to find better tests or procedures for diagnosing a particular disease or condition.

There is also growing interest in testing different ways of giving people health information, to see which is most helpful to them in making decisions or understanding and managing their condition. 

Information and quality of life interventions' to help people learn about their condition and help them to self-manage their health better and improve comfort and quality of life. Interventions may include finding the best approaches to help people control their symptoms or improve their quality of life by testing how a particular diet affects a condition. 


Sophie (aged 12) was randomised to take part in a one day trial to develop an intervention for...

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Age at interview: 12
Sex: Female
Age at diagnosis: 3
I’m not sure like who approached me. But we had to, like we had to group together with a load of other people with diabetes. And I think it was the diabetes nurse that showed us round. When, when, like we had to like fill like loads of like, like questionnaires, fill them in and like tell her things about diabetes and what you like about it and what you don’t like. And like for like dinner we had like, when it came to dinner we had like fruit, like passion fruit and loads of different ones. And I think there were sandwiches there and loads of very healthy food.
They like said like how you could like keep your diet up, if you see what I mean. Like how you could like keep control of your blood glucose levels. And like when, like when, what, what to do, like how to stop you like going into hypos and hypers with your diabetes and that.
To like, I think it was like to, like you, like to us to understand like what the bad things are about stress and what the good things are. And then like the bad things about like what do we feel about it. And then the good things about it.
And what was the questionnaire that you filled in? What was that about?
It was like about like how do we feel about our condition. How old we are. And like the contact numbers and signatures and all that. And like as you go through it we had to like tick like things about like, how do we feel about something like our diabetes for instance. And like, there was like three columns. Okay with it, good, very good. And that’s it, like there were circles and we had to tick each one.
What, what sort of questions did you have about that?
Like were we nervous like coming to the thing to fill in like a load of things, things what, like nervous when we were coming because we’d never met other children before like us? And like are, are we like, are you stressed or confused about like anything about like your condition?
And is that things that they asked you? Was that on the questionnaire, was it? And how did you respond to those things?
I said sometimes confused with it because like there’s a lot to it. Like you’ve got to like take your blood sugars if you, and like you’ve got to work out whether you’re low, you’re high or you’re fine.



Joe took part in a trial to assess home versus hospital management at diagnosis of childhood...

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Age at interview: 15
Sex: Male
Age at diagnosis: 15

Well, they explained what they were going to do in the trial. They explained like about diabetes. And they said, “The trial is just to see how you cope with like, with diabetes.” And in hospital I think it was better because if I needed any, if I had any questions I could have asked them and stuff. But I think if it, if I had the trial at home I would have been able to like, you know, deal with it on my own more, instead of like asking people.

So was there a choice?

No. The organisers, they choose for you.

They choose for you? So you could you have gone home at all?

could have gone home. But I think it’s like they randomly choose people to stay in hospital or go home. And I was chosen to stay in hospital.

I was going to say, I was wondering whether you were randomised. And did they mention about the, explain about the, that grouping in those groups to you? Why they were having those?

Yes, they said, they mentioned that they wanted to see how people dealt with it in different like situations. Like when I was in hospital, if like, you know, at home, to see how people coped with it more. If you got put in hospital it was just for the doctors to help you really and stuff.

And how did that feel, you know, when you were, you sort of, you were diagnosed and then you were, then you were asked to go in to a trial? How did you feel at that time? Because it must have been a bit overwhelming?

Yes, I was really overwhelmed, I was shocked. And my mum was shocked as well. And it was it was upsetting when I first found that out I had diabetes. But then I thought, “Well, it’s like, it’s a speed bump and not a stop sign. So it’s not going to stop me.” But then the trial, I just, I felt happy to be in the trial because it’s to help me and to help other people, research and stuff. So, yes, I was happy I got put in hospital though, because I was a bit shocked at the time.

And, like you say, one of the reasons you wanted to take part was to help yourself. In what way do you think it was going to help you and help research?

I think it would just help me to understand diabetes and like how to deal with it more, because I was really shocked when I found out. And it did, the research is, because I’ve been through the, you know, the shock of having diabetes, and when other people get diagnosed it’s just like unexpected and stuff. And the research will help people deal with it I think.

Other types of trials can include those that find the best surgical interventions and trials which compare the frequency or intensity of a treatment, such as radiotherapy regimens and even Psychological therapies' which help to find out how best to provide psychological support.

Some young people we interviewed were invited to take part in non-randomised trials - see ‘Other types of medical research’. These types of trials are also important in improving treatments and advancing knowledge.

Last reviewed March 2017.
Last updated July 2014.