The Research Files Episode 12: Dr Chris Harvey on delayed school start times

Hello, I'm Jo Earp. Thank you for downloading this podcast from Teacher. Welcome to this month's episode of The Research Files. Today I'm speaking to Dr Chris Harvey, Education and Outreach Officer at the Sleep and Circadian Neurosciences Institute at the University of Oxford. He's part of a team tracking 32,000 high school students in a year-long study to see if starting the school day later has an impact on student achievement levels. Dr Harvey joins me now on the line from the UK.

Jo Earp: Welcome to The Research Files.

Chris Harvey: Good morning and thanks for having me.

JE: Can you explain just briefly then what we mean by circadian rhythm and its importance. I read that your colleague, Professor Russell Foster, has said that getting a teenager to start their school day at 7am is a bit like asking adults to start their work day at 5am.

CH: Yeah, exactly. The circadian rhythm basically is your biological rhythm - it's your biological clock. What the circadian rhythm does is make sure that all your systems are working in sync with each other, but also working in sync with the external environment.

What happens during adolescence, why they have such a hard time getting up, is this rhythm actually delays. Now, what that means is that during adolescence, from the age of about 10 until about 21, is your biology is more prone to falling asleep later in the evening and therefore getting up later. However, society often still demands that you have to work in a sort of 9 to 5 window, which means that adolescents are then often very sleep-deprived.

The issue with this is that we know sleep deprivation leads to various illnesses, in the long term, but in the short term it will affect your moods, your ability to engage and therefore your ability to learn. So it can have a serious effect on education.

JE: Now, I mentioned there in the intro that you're part of a team tracking 32,000 high school students. What's the aim of that – it's called the TEENSLEEP study isn't it?

CH: That's right. TEENSLEEP is a large, randomised controlled trial. We have two different interventions and what we're looking at is, on one arm, to see if delaying the school start time – starting lessons at 10am versus 9am – if that improves academic performance in GCSE exams (which people take in the UK when they're about 16).

But we're also looking at sleep education, to see if teaching adolescents about good sleep practices - how to get sleep, how to maintain good sleep, how to deal with stress so that it doesn't interfere with your sleep – if that improves sleep and what effect that has on attainment; and also looking to see if these two interventions combined help the effect.

JE: This is a year-long study. What will it actually involve in terms of how it will work, the mechanics of that, what will you study and what will you be looking for and what information will you collect?

CH: It's a really big study. Delaying the school start time, schools will do that for a year but the study itself will actually run over four years and that's how long it will take us to complete the full thing. What we're doing initially is piloting the education intervention and then after that we'll roll it out across 100 schools in the UK.

What it will involve really is schools being randomised to different groups: one group doing a delayed start time; one group getting education; one group getting both; and one group getting no intervention, so that we can really assess the effects. But we'll also be looking at, other than the academic outcomes, general health and wellbeing measures and also sleep measures.

There are different ways that we're doing this. A large part of it is survey data, because of the numbers that we're including in the study it's very difficult to look at anything other than questionnaire data, so we'll be doing surveys three times a year across the interventions looking at general wellbeing, sleep, circadian preference - whether people in this study tend to be more prone to being more active in the evening or in the morning – and also sleepiness.

Then in a sub-sample of people … we're working with a company called Jawbone (who make the Jawbone Up devices) and what these devices measure is activity and from that we can look at the sleep/wake cycle. So, on a sub-sample of students in each school, we'll be assessing their sleep/wake patterns in this more detailed way, and also taking indices of stressor activity by looking at heart rate and also looking at the circadian rhythm in these people by measuring their temperature, because temperature has a very distinct circadian pattern throughout the 24 hour day.

JE: This is a follow up isn't it to a smaller trial that took place in Monkseaton, which is north east England I think, can tell our listeners a little bit about some of the findings from that trial?

CH: We got some really promising results from that trial. What we found was that the delay in the school start time did in fact increase academic performance in the GCSE examinations and that this increase was more pronounced in individuals who come from a deprived background – who have a lower socioeconomic status.

We're not really sure why that is the case, it may well just be because people who come from deprived backgrounds tend to have a lower baseline in terms of academic performance and therefore it's sort of easier to raise that. But overall, the school improved and we'll also be looking at other things besides academic achievements in the schools. We would also expect this to possibly have an impact on general health, so we would expect the number of absences to decrease for example and, as sleep improves, we would expect behavioural issues to become less of a problem in the classroom.

These things weren't measured in the pilot study, but they will be measured in the big trial now and it could be that these things account for some of the improvement as well, as well as the improvement in sleep.

JE: Obviously you're yet to start the research, I understand that starts in September. But, what are some of the possible implications of TEENSLEEP for educators – I suppose at a very basic level it could change completely the way that schools open and close, the opening and closing times?

CH: Exactly. There are some really interesting discussions to be had, once we have the data, at a policy level. Is the way we're teaching appropriate? And should we be teaching to suit the people that we're teaching, rather than teaching to suit the people who are delivering the teaching?

It's very well established that adolescents have this pattern of biology and so it may be the case that they'd perform better if we did let them sleep in a bit later and start their learning a bit later. So, yeah, at that very basic level that may be the change, but I think there are really interesting discussions to be had around that.

Of course, there's the counter-argument that by letting them start later, you're not really preparing them for the real world. So, I think from this study there's going to have to be then follow-up studies to see how the people in the sample who did get the delayed start time fare when they then go on to university or into working life. That's the thing with research, there's never just one study. It always raises 500 other questions.

JE: That's true. Well, I'm sure there are lots of educators out there – and teenagers who'd welcome an extra hour or two in bed on a school day – who'll be watching it with interest. Good luck with the study, thanks ever so much for taking the time to speak to The Research Files.

CH: Not a problem, thank you for having me.

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What opportunities are there in your curriculum to educate students about the benefits of sleep?

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