Cohort Studies

What time commitments and other practical issues are involved in cohort studies?

Before deciding whether or not to join a cohort study, it is important to think about the time commitment and other practical issues involved. These factors will vary from study to study, and the people we spoke to had different ideas about what they were happy with. The three main aspects that people spoke about were:
 
How long it takes to do the study activities;
How often they are asked to do study activities and length of study; and
Where they will do study activities (e.g. at home, at a hospital, at a GP surgery, at a university, or elsewhere)
 
Time taken to do study activities
 
Cohort studies can involve lots of different activities and these can take up varying amounts of time. Alan Z says his appointments last about 30 minutes. Brian has had visits from researchers to carry out tests: “it’s not arduous at all, it only takes an hour or so all in. In the scheme of things, that’s nothing”.

Gill says it takes about 30 minutes to complete the annual questionnaires for her study and then she posts it back to the researchers.

Gill says it takes about 30 minutes to complete the annual questionnaires for her study and then she posts it back to the researchers.

Age at interview: 79
Sex: Female
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And were there any downsides?

I don’t think so, really. It’s, it wasn’t a difficult form to fill in and I was happy to take the time.

Okay and does it ever feel like a burden when you get that through the post? Do you sort of think, ‘Oh I’ve got to do this again and it’s another thing?’

No, I don’t, I feel, ‘Oh this is interesting. I wonder what questions they’ll be asking this year?’ because they’re often different.

I think I’d say, “Go for it”. I mean it’s a, it’s not a difficult thing to do. It takes about, I suppose, half an hour or a bit longer to fill out the questionnaire and, and you just send it back. I mean, you know, it’s not hugely onerous from the point of view of time or effort, so I’d say go for it.

 
But research activities could also be time consuming. Keith had one appointment for a study which took five hours and involved “a battery of tests”. Salma remembered one questionnaire which took at least 1.5 hours to fill in. She didn’t mind though because she was waiting for an overdue appointment and felt the research would ultimately benefit “the wider community”. For one study, Malcolm wore a heart monitor for five days, took his blood pressure regularly and wore a Fitbit to record his level of daily activity. 
 
The frequency of study activities and study length
 
The number of visits and frequency of completing activities varied across the studies. In some studies, this changed over time for each individual. Alan Y had follow-up appointments every six months initially, then once every year, one appointment at five years and one final appointment at ten years. Some studies planned to follow participants for their whole lives whilst other studies, such as the one Alan Y is part of, have a set number of years that each participant is involved.
 
Whilst each activity or study visit might be quite short, the amount of time involved could add up over many months or years of taking part. The people we spoke to were mostly happy with this arrangement. Linda was proud to support medical research and, in her study, it only required participants “to give up a small amount of your time to do it”. Jennifer agreed: “it’s not any hard work. It’s nothing”.

Alan Z is part of a five year renal (kidney) study. He doesn’t feel this is too long a commitment, and that it is a good length of time for the researchers to gather data.

Alan Z is part of a five year renal (kidney) study. He doesn’t feel this is too long a commitment, and that it is a good length of time for the researchers to gather data.

Age at interview: 86
Sex: Male
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Yeah well, I had to do it over a certain number of years because to get a comparison of how you’re functioning over a period of time. I suppose two years would not be enough; three years would hardly be very much about it. I suppose five years, you’ve got a broader landscape to see how the actual performance of the kidneys is actually bearing up.

 
A few people, like Elaine and Jade, had decided not to enrol or stopped taking part because of time constraints and other commitments. Elaine decided not to join a biobanking study because she was already involved in other medical research and the appointment times would have clashed. Jade and her sister stopped taking part in a twins study because they found some questions and tests “intrusive”. 
 
Some people talked about extra commitments that might make it harder to take part in a cohort study. Mr S thought time was a big factor for many people and especially for parents: “the type of lives that we live are very busy”. Nadera had three children under the age of five when she first became involved in a study. She said it was hard to do extra activities with babies “when they needed me, crying, nappy changing, all this”. Keith said one factor for him was that “I was about to retire so had a bit more time on my hands”. Isobel had to stop taking part in a study about asthma when she changed jobs to shift work and could no longer go to the hospital on her days off.

Being retired, Anthony feels he has the time to take part in a study. He thinks it is important that younger people take part in medical research as well though.

Being retired, Anthony feels he has the time to take part in a study. He thinks it is important that younger people take part in medical research as well though.

Age at interview: 76
Sex: Male
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Yeah, well, I can’t see any point not participating because I think it’s, you know, if it’s going to help research or other people, just participate. I can’t see any reason not to, unless you are so busy that you can’t afford the time not to, but being a retired old man [laughs] I don’t, I can’t see any reason not to. You know, it’s, I think I would encourage everyone to participate if they could.

Okay.

It needs, probably needs younger people because from what I saw most of the people were my age that were going in or waiting.

Okay, so…

I should think you ought to try and encourage younger people to participate.

Eisha says taking part in research is a time commitment and it can become overwhelming if you are juggling lots of activities in your life.

Eisha says taking part in research is a time commitment and it can become overwhelming if you are juggling lots of activities in your life.

Age at interview: 32
Sex: Female
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I think it’s just the commitment. You need to give your time, like, you know, I’ve got family, I’ve got kids, I’ve got little ones, I work, I volunteer. Even in my work I volunteer. I do provide massages to elderly people whenever I can. It’s just that you need to commit for the time and sometimes I believe people who are participating into some sort of a research, because it’s a sense of responsibility and it is a commitment, it sometimes it gets overwhelmed if you’re everywhere and if you are, if you’re giving more than sometimes it’s more than what is being required. That is it.

Douglas can adjust the dates of his next follow-up appointment if needed. He is retired now but feels he could have told his work he was needing time off and this would have been fine.

Douglas can adjust the dates of his next follow-up appointment if needed. He is retired now but feels he could have told his work he was needing time off and this would have been fine.

Age at interview: 70
Sex: Male
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I was two years in, I’m two years into it.

Yes.

Not, it’s not a big commitment because I can adjust the dates of it, you know, they’re far ahead so I can adjust the dates. So we can change them but because I’m now retired it’s easy, I can take time off, it doesn’t matter. But when I worked, I was in a senior position, so I said, “Look, I’m doing this and that’s the end of the story,” and everybody said, “Okay”.

Gareth took annual leave to attend a study visit. He didn’t think he could tell work it was a medical appointment and instead tried to frame it as a community service activity, but in the end had to take it from his holiday entitlement.

Gareth took annual leave to attend a study visit. He didn’t think he could tell work it was a medical appointment and instead tried to frame it as a community service activity, but in the end had to take it from his holiday entitlement.

Age at interview: 49
Sex: Male
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Having done this now, you know, if I was invited back to something similar to insulin then I’d probably be more likely to give it a second, you know, give it some serious thought. I mean, the downside to it is that I don’t think - they did ask me if I’d come back and give some more biopsies, but it’s, the problem is it takes half a day out of my annual leave and having already taken one to do that, and lost a day with all the snow at the beginning of the year I’m running low on annual leave. So it’s, you know, one of the things that would limit it is just how much holiday I have in any particular year or whether, or whether they can tie it into when I’m actually on shutdown. So that’s actually a limiting factor at the moment.

 

Yes. I was tempted to take it as a sort of medical appointment, which I could say without lying [laughs], but I didn’t. That wasn’t right. One thing my company does support is actually working in the community - and I did fly that past them and say, “Oh, you know, it is a community service”. But they weren’t too keen on that either. I didn’t push the medical side of it. I sort of just said, you know, “I’m doing a bit of research. You know, would that count?”

 
The locations of study activities
 
Sometimes people took part in study activities at home. This included questionnaires which arrived in the post or were accessed online, but also sometimes study staff came to the participant’s house. Alan Y’s study included both home visits from a research nurse and visits to a hospital for tests. He found his blood pressure was lower at home because he was more relaxed there.

A researcher visited James and his wife at home to complete a follow-up. Previously he had gone to a hospital to complete activities for the study.

A researcher visited James and his wife at home to complete a follow-up. Previously he had gone to a hospital to complete activities for the study.

Age at interview: 76
Sex: Male
Age at diagnosis: 66
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And you said the researchers came to your house last time...

Yes.

…they did the ten-year review. Is that normal or would you have to go to hospital?

Normally, I’d go, I went to the hospital for the previous ones but because my wife is also on the study would you believe, because she had a minor stroke just over a year ago, 18 months ago I think, but she can’t, it’s so difficult, she’s in the wheelchair, getting to them and so they said, “No, no, we’ll come to you”. And from whether they change their modus operandi, I got a letter saying, ‘You’re due for your ten-year follow-up, could we make an appointment to come and see you?’ I didn’t even have to say come and see me.

Emily completed a questionnaire over the phone for one study and it was difficult remembering all the tick box options without seeing them written down.

Emily completed a questionnaire over the phone for one study and it was difficult remembering all the tick box options without seeing them written down.

Age at interview: 68
Sex: Female
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Are they presented in a kind of easy to fill in kind of surveys?

Yes except the one, they did some telephone interviews from the, on the Alzheimer’s one and basically they were saying, do you have sort of like they say suicidal thoughts and matter and they just say, your choices are, you know, never, occasionally de de de de [illustrates ticking of a list] and by the time you’ve got to the end of the list I’ve forgotten what the list was. So I said, “Hold on a second, let me just write down that list. Okay now ask your question,” and so it was actually quite difficult to do because I couldn’t, I’m much better with visual things. I couldn’t keep them in my head.

So this was a telephone interview?

Yeah telephone interview that was basically her filling in a multiple-choice question, but I couldn’t see what the answers were. It would have been much better if she had sent me, you know, “Now turn to card four,” you know, what I mean. “Here are your answers, now let me ask the question,” do you know what I mean?

Jade stopped taking part in a twins study when she was 12 years old. She didn’t like being separated from her sister to complete the tests at home, and she would have liked opportunities to meet other twins.

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Jade stopped taking part in a twins study when she was 12 years old. She didn’t like being separated from her sister to complete the tests at home, and she would have liked opportunities to meet other twins.

Age at interview: 25
Sex: Female
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Oh yeah, well no, we did them separately. That’s another one of my memories. Being-, not being allowed to sit together to answer the questions. Which, looking back it’s obviously the entire point of it ‘cos you’re not meant to copy each other [laugh].

But it was quite a-, I suppose it would have been different to what we were used to and probably a lot more formal.

I think it’s a shame that we stopped participating. I wonder when that happened if somebody actually sat us down and talked about why they do twins studies, and what they were using it for.

I don’t know if that happened.

Yeah.

And I don’t know if-, if they did that, whether it would have made a difference but also, I remember we only ever did this at our home. There was no-, as far as I remember, we never had any kind of interaction with other twins or kind of anything more like that. That might have made us feel part of something or feel like it was fun.

Yeah.

It was more like they get sent to your house.

Yeah.

These packs. I’m not sure if researchers came to our house or not.

So I guess that’s why we stopped.

 
Other times, participants were asked to travel to the researchers to do some of the study activities. This could mean a long journey to get to where the researchers were based. As Alan Y pointed out, the journey plus parking can be quite stressful at some hospitals. Douglas also travelled for his study and although it wasn’t very far from where he lived, “in the morning, you hit so much traffic. It’s a nightmare”. Emily had asked the researchers if it was possible to consent into the study over the phone or by video messaging, but they said no and she found this appointment “a bit tedious”.
 
For Linda and Alan, travelling to the hospital or GP surgery to complete research activities was less of a concern because they were within walking distance. Malcolm wore a heart monitor for five days for a study he was part of. He thought it was helpful that he could just put the equipment in an envelope and hand it back to his local GP surgery, rather than return it to the researchers based at a hospital.

Emily finds it very convenient that the researchers come to her local GP surgery to do the follow-ups.

Emily finds it very convenient that the researchers come to her local GP surgery to do the follow-ups.

Age at interview: 68
Sex: Female
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Well we go to see them in the GP’s surgery. It’s definitely down to annual now, I can’t remember how frequent it was before, you’d have to ask them that.

Okay so you don’t, you can’t remember.

It might have been every six months, it might have been every three months, it might have been more frequent, but it didn’t matter, it was all very convenient.

It was convenient for you?

Yes because it was here in the village.

 
Some studies will pay the travel expenses of participants. This was the case for Linda, Douglas and Margaret. George was part of a study which arranged a taxi to take him to meetings and then return him home again. Teresa had attended “a big visit” to a hospital for tests which required her to fast (not eat). To get to the hospital, she had to travel a long way, and the study paid for her hotel the night before.

George is involved in stroke research. A taxi is arranged to take him to meetings and then return him home afterwards.

George is involved in stroke research. A taxi is arranged to take him to meetings and then return him home afterwards.

Age at interview: 42
Sex: Male
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Yeah, and they took my name, they took my name from there, so they send me invitation to come, to come in a meeting.

Yeah and they send, they send cab here to take me to there, take me to a meeting.

And you go every Tuesday?

Not every Tuesday, every, every month. They tend to every two months.

Okay.

So, when they come to take me here and they bring me back, they bring me back.

By taxi, they take you by taxi.

Taxi, yeah.

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