This chapter uses material from an Open Access article previously published by the research team (see Armstrong et al., Br J Gen Pract 2024;74:e34–40. https://doi.org/10.3399/BJGP.2023.0162 https://doi.org/10.3399/BJGP.2023.0162). This article is published under licence to British Journal of General Practice. This is an Open Access article distributed in accordance with the terms of the Creative Commons Attribution (CC BY 4.0) licence, which permits others to distribute, remix, adapt and build upon this work, for commercial use, provided the original work is properly cited. See: https://creativecommons.org/licenses/by/4.0/.
We conducted a process evaluation of the HABIT SRT intervention in line with the UK Medical Research Council (MRC) process evaluation framework in order to understand intervention delivery, fidelity, and acceptability from the perspective of patients, PNs and GPs or practice managers.57 Process evaluations are recommended in trials of complex interventions and, in this study, we aimed to explore how nurse-administered SRT in primary care worked, by examining implementation, mechanisms of impact, and contextual factors. Implementation explores how the intervention is delivered and what is delivered. It includes the training and resources available to the intervention team as well as the fidelity of delivery and any adaptations to delivery. Mechanisms of impact explore participants’ reactions to the intervention, including perceived benefits as well as unintended or adverse effects. Finally, contextual factors can affect implementation and help us to understand the potential for sustaining and scaling the intervention more widely.
Methods
Design
The process evaluation used a mixed methods design, integrating data from qualitative interviews and quantitative data collected from intervention participants.
Qualitative interviews
Semistructured interviews were undertaken with patients who had received SRT, the nurses delivering the intervention and the practice managers or GPs at the practices involved. The interview schedules can be found on the NIHR project page. The interview schedules were developed using the three key themes of the MRC process evaluation framework, namely (1) implementation – did the patient understand what was being asked of them; (2) mechanism of impact – how did the patient feel about the intervention and (3) context – how easy was it for individuals to integrate the intervention and how sustainable was it. Similarly, the interview schedules for the nurses and practice managers/GPs sought to understand how well the intervention met their needs and could be integrated into practice.
We aimed to interview 15 patients, five per region in the three areas, Thames Valley, Greater Manchester and Lincolnshire, where the trial took place. Patients were asked during their baseline assessment appointment for consent to be interviewed. Interviewees were selected from the list of patients who consented and completed the SRT intervention < 6 months prior to the interview. In addition, participant sex and age were considered to ensure that a wide range of participants were selected for interview. We also interviewed some participants who were close to their 6-month outcome assessment, which was important as it allowed us to determine how they felt about longer-term adherence to the intervention. Nurses from all three regions were also interviewed. Finally, practice managers or GPs from each participating practice were invited for interview, and those who consented were asked about their perceptions of impacts on the practice and the sustainability and scalability of the intervention. All interviews took place by telephone and were digitally recorded and transcribed. Interviews were conducted by two trained and experienced non-clinical academic qualitative researchers (JP, SA).
Quantitative data
We compared patient interviewees’ qualitative perceptions of the intervention with two quantitative measures. These were baseline ISI and the SE recorded at baseline with a 7-day sleep diary, and during each week of the nurse-delivered intervention. ISI is a seven-item self-reported questionnaire, scoring between 0 and 28, which assesses the severity, nature and impact of insomnia, while SE is the time asleep divided by time in bed multiplied by 100 (to give a % value), which generally increases in participants for whom SRT is successful.
Data analysis and integration
Qualitative interview data were examined using Framework analysis supported by NVivo 12. Two members of the research team (SA and JP) undertook the interviews and checked the transcripts, which were transcribed by an independent service. Through familiarisation with the transcripts, examination of the interview schedules and the three key domains of the MRC Framework, an a priori set of categories was developed to form the basis of the framework.
Transcripts were then coded independently (by SA and JP) and codes categorised using NVivo 10. The interviews proved to be a rich source of data and therefore an ‘other’ category was included in the framework to ensure that relevant data that did not readily fit into the framework would not be lost. While the categories were applicable to each of the groups interviewed (nurse, patient and PM/GP), the codes were specific to each group as outlined in A. Three members of the research team (SA, JP and NS), one of whom was independent of the initial analysis, agreed the final themes presented in the results.
Joint display
Relationships between qualitative findings, notes that nurses made during treatment sessions, and quantitative measures were explored and presented using a joint display. This table allowed us to directly compare the patients’ perceptions of SRT with any noted changes to their sleep as measured by changes in their SE and nurse reflections following treatment sessions (Table 32).
| Area | Baseline ISI | Baseline SE | SE at sessions 2, 3, 4 | Nurse record summary | Patient perspectives |
|---|---|---|---|---|---|
| A | 16 | 64 | 90, 92, 96 | Largely positive participant has coped well with intervention and has shown marked improvement. | I think I noticed it really quickly within a couple of days. Because my sleep is always broken, I would go to sleep, and I would continually wake up; but I was going to sleep and then waking up with my alarm clock. I think that happened from day 3 onwards. And to me that hadn’t happened in years. I’ve never been woken by my alarm clock. |
| 22 | 57 | 91, 95, 95 | Participant found the intervention hard to start with but showed improved sleep patterns by session 4. | Although it took down the amount of times I was waking up, I don’t really think it helped my quality of sleep that much. I was still feeling tired during the day, so I never napped during the day; it’s something I don’t do. I’m still feeling tired by about mid-afternoon. But I soldiered on through and kept going with it. So, it basically got down into the fourth week when I’d gain an hour and a half; was going to bed earlier, but I was still getting up, still waking up, one or two times a night. It wasn’t normally for very long. | |
| 16 | 54 | 59, 57, 57 | Participant found the intervention very difficult to maintain, especially the ‘going to bed’ time. | I’m obviously quite a bad sleeper anyway. But by the third week, I could understand what the therapy was all about. It was obvious to me that this was going to work for some people. I can’t say it was working for me. It did some nights, but some it didn’t. | |
| 21 | 76 | 89, 90, 82 | Patient took sleep medication that interfered with later ‘going to bed’ time, leaving them feeling drowsy and tired. | The going to bed was fine, and I stuck to that really well. And then the getting up, I succeeded most of the time, because I’m on trazadone, that sedates me for about a 9-hour duration, from the dose I’m on; therefore, if I’ve only got 6 hours in bed, that sedated effect is going to continue longer than that, and that made it very difficult. I did succeed in waking up at that 6 o’clock time, almost every time though. | |
| 16 | 72 | 84, 82, 82 | No notes available. | It didn’t particularly work well for me, because I think my sleeping problems were menopause-related, and I don’t think it worked particularly well. I think that was the cause. So, the nurse was great; very positive; the meetings were good; so, I was clear what was happening. | |
| B | 25 | 66 | 79, 82, 82 | Participant struggled with new wake-up times but showed some improvement. | My hardest bit was the getting up at the time she wanted me to get up; and I couldn’t do that. I was getting up way too early; way too early. And then all of a sudden, bang, it stopped, and I reverted back. If I’m honest, I think it was a waste of time for me because it was only 4 weeks. If it had been a lot longer, then I think going around my head, I said it was all psychological, I think I would have been able to get my mind really in a mindset; but after 4 weeks, no, that was it. |
| 8 | 79 | 84, 86, 86 | No notes available. | I think if you look at the whole 4 weeks, it’s quite … explaining I’m a light sleeper etc., yeah, I was getting longer periods of sleep. If it was only an hour and a half before I woke up; on occasions 2 or 3 hours; that was good for me because generally speaking, if I was to take an average, a normal week without doing the programme, it is at least six or seven times a night that I wake up, and then I have a difficulty getting back to sleep. So that element of it certainly worked, yes. | |
| 13 | 78 | 92, 96, 93 | No notes available. | Like I said, the first week, I was struggling, and I was getting anxious because I wanted to go to bed. I felt – No come on, do something. I was quite strict on myself because I thought – It’s going to be for the better for you. So, I did shout at myself. | |
| 18 | 75 | 88, 81, 87 | Participant continued to wake multiple times at night but overall showed an improvement. | … initially the restriction was quite severe wasn’t it? We start at 6 hours of sleep. Or I don’t think I was tired. I do like to nap. I didn’t nap during the whole of the 4-week period, and actually beyond. And yet, I didn’t feel as though I was going to need to. | |
| 17 | 53 | 82, 82, 86 | Participant initially had increased tiredness but gradually this improved. | I think I got something out of it: sometimes I find it easier to go back to sleep when I’ve woken up. Other times I haven’t, I’ve found it quite hard. | |
| C | 21 | 66 | 52, nr, 83 | Sleep being disturbed by external influence; however, overall showed some improvement. | Certainly, from my perspective, it has improved my sleep quality, whether we can extend the sleeping hours a little bit, I don’t know; food for thought for the future, but regarding other people, I would certainly recommend that they try something because you can’t continue being sleepless; It’s to your detriment in the long term. |
| 16 | Missing | 100, 89, 86 | Participant struggled with later ‘going to bed’ time as felt too tired to stay up but some improvement in quality of sleep mentioned. | Well, I don’t know if it was just catching up with my sleep, you know. The first week I did sleep really well because I don’t think I was given enough sleep. So, I don’t know, it’s really difficult to say, but the second week and third week, I felt exhausted. Really exhausted, so. Then felt alright again this week. | |
| 18 | 62 | 93, 96, 96 | Participant struggled with not napping in the afternoon. Reduced nap time to 20 minutes and has shown some improvement overall. | I’ve done as requested. You know, gone to bed when I should, got up when I should, but I still fall asleep in an evening, sometimes I’ve just gone, do you know what I mean? And my head, in the beginning, was feeling terribly woolly: sometimes didn’t think it belonged to me. | |
| 22 | 50 | 95, 92, 94 | Found first week difficult but once settled in routine slept better and had more energy during the day. | I mean the first week, getting up, the alarm used to go off and I’d think – oh god, now I’ve got to get out of bed. But I’ve sort of forced myself to do it. Because I thought – If this is going to work, I’m going to have to stick to it. And I did. I mean after you get over that initial first week, you start to feel the benefits of it. | |
| 5 | 77 | This participant did not complete all four SRT sessions due to an underlying health condition that was diagnosed during the intervention. | It wasn’t actually my, well it was my decision as such, but it was the nurse actually who said – I really don’t think you should be on this. Because we had met up, I think it was for the last time, and we were talking about sleep routine, and looking again at my sleep diary, and she said I really don’t think it’s anything to do with how much sleep you are getting, it must be something else. And I was taking to her about how I feel in the morning, what time I was going to bed, the routine that she had told me to follow, and that is when she said I should get a blood test, rather than do the sleep clinic. | ||
Results
The initial aim was to recruit five practices per region with equal numbers of interviews of patients, nurses and practice managers or GPs from each. We interviewed 16 patients, 13 nurses and 7 practice managers or GPs. Interviews were conducted by telephone and were 30–60 minutes in duration. Patients ranged in age from 19 to 74 (mean 56) years, including 7 male and 9 female interviewees, all of whom identified as White British. Patients are designated in the results by region (A, B, C), gender (M, F) and age, for example Patient AF57. Nurses are designated by region and whether they were a Clinical Research Network (CRN) nurse or a practice nurse (PN).
Due to lack of availability of nurses at specific practices two regions utilised research nurses (employed by their LCRN) rather than practice nurses. ICRN research nurses covered more than one practice and therefore 13 nurse participants were interviewed. Finally, in two regions practices formed consortia, with several practices falling under one management group, so seven interviews were undertaken in the practice manager (six interviews) or GP (one GP) category.
Themes are listed under implementation, mechanisms of impact and contextual factors.
Implementation of sleep restriction therapy
Patients lacking experience of behavioural therapy did not know what to expect
Patients did not know what to expect from SRT. Most had no previous experience of behavioural therapy and they had not been offered this type of therapy for insomnia before.
No, it was the only sort of formal treatment I’ve had. I’ve tried things like relaxation, and things like that, but this was the only sort of scientific treatment I’ve had.
All the patients hoped for improvements in their sleep pattern and daytime symptoms. They expressed how uncomfortable they felt if they had not slept well.
The only thing I really hoped that would come out of it would be improvement in my sleeping patterns; sometimes, if I have not slept very well, I wake up in the morning and I am really quite dizzy which is very uncomfortable and is horrible.
Overall, patients hoped that their SRT would make them feel less tired and more refreshed in the mornings:
I had the hope, rather than the expectation, that it would make me feel better in the morning; I would feel fresh, less tired.
Appointment preparation and preferences
Nurses felt prepared and were supported with adequate training and tools enabling them to deliver SRT effectively:
It was quite straightforward, and obviously we were provided with a PowerPoint presentation to go through; so that first initial consultation with them; so that was really helpful.
Both nurses and patients highlighted flexibility in appointments as important, particularly where the patient worked full time.
Yeah, I’ve just had one chap who missed his appointments because it had totally gone out of his head, and I just re-booked him for the next week; and he came to that one.
… they [SRT nurse] were really good and arranged a time to suit me because I work full time.
The benefits of face-to-face appointments for nurses and patients highlighted the relevance of non-verbal cues and patients maintaining motivation.
I think the face to face is probably better because you can see a reaction from someone.
So, I had a one-to-one meeting with a nurse, and I felt that those are really beneficial for me in terms of maintaining that treatment. For me personally, I don’t think I would have done it without the one-to-one.
You absolutely can’t do the first one on the phone. [Although] From a patient perspective, it’s very convenient I guess, because they don’t have to come back to the practice. It’s not the first time I’ve done phone stuff. I don’t mind it. I’ve got to say, maybe I prefer seeing patients, but I think it works fine.
Accommodating and tailoring therapy
When patients had difficulty implementing SRT, and particularly where their routines impacted on intervention delivery, nurses were able to modify SRT to the patient.
There’s only one really out of the three, where I think there was a bit more tweaking of the times, if you like, and changing; purely because their routine was different.
We tried to come up with a bit of a solution to it because not everybody is the same, so I felt it would be easier for me if I could knock it off in the morning. So, I didn’t mind getting up at 5.30 a.m. rather than staying up.
The SRT required individuals to calculate their SE. For some participants, understanding the calculations involved was challenging. Nurses found that they would need to tailor the sessions to individuals, with some sessions being significantly shorter or longer than expected due to the patient’s ability to comprehend the process. However, this did not represent a major deviation from protocol and did not appear to indicate poor implementation.
For someone who isn’t as bright or able to take on information, you then have to amend the way that you are giving that information. I did have to change some of the terminology.
It varied definitely. Some patients were able to engage very quickly, and the sessions could be done within 20–25 minutes because the patients were well engaged, able to understand the maths, able to understand what we wanted from them, how it was going to influence their sleep. Other patients, however, were very surprised about what they were expected to do, finding the concept very difficult.
Negotiating sleep timings
Interviews also highlighted a level of negotiation between the nurse and patient particularly around bed and rise times. Nurses sometimes allowed an extra 15 minutes of time in bed, but the protocol allowed for minor amendments to SRT to support a patient-centred approach, so this flexibility did not compromise fidelity.
And I said I was really struggling to get up at 5 a.m. in the morning at the moment. So, we moved that to 5:15 last week.
I want to go to bed! So, we negotiated that way around.
I have actually played around with it (flexibility in sleep times) if they had been over 85%; particularly as I have got more used to it. I think initially when you start something; you get worried about how strict you have to be.
Learning to deliver despite complexity of sleep restriction therapy
Initially delivery and understanding of SRT involved a learning curve for both patient and nurse, who often adopted a collaborative approach to learning:
It was a learning curve for both the nurse and myself; between us we worked out what was needed.
Nurses felt that the intervention, although quite complex, was easy to deliver with practice.
I think I was probably quite nervous to start with; but I think that is probably like most things, something new, and you do have teething problems when you start anything new, and I don’t know about pressure. I think it was just being very honest with the patients when they first came, and just said that this was at the very beginning, we are going to go slowly, sort of thing, and to just bear with me; and I think everyone is very understanding really, if you are open with them.
Patients indicated when they were able to calculate SE but suggested that simplifying this might help retain people on the intervention.
She took me through the calculations, on what we filled in on the form; so I could have an idea how to work them, but at home it took me a long time to do all the calculations.
I expect other people would drop out because it took them a lot of time doing the calculations. It’s quite fiddly. So, if there is a lookup table, or something like that that you could provide, it would make life a bit easier because that was the biggest challenge for me, was doing the calculation.
Two of the SRT sessions were delivered over the phone and for some the challenge of the calculations was compounded:
It is very difficult to explain maths over the phone to a patient if they really struggle to understand it.
Challenge of delays
For some nurses there were delays between training and seeing their first SRT patient, which increased the challenge of delivery:
I think that was difficult because to do training and then wait, like quite a long time, till you are actually, physically seeing patients.
In one case, nurses paired up to deliver SRT for their first patient to boost confidence. This was a divergence from the delivery protocol (but agreed by the team in advance) and would only have been problematic if subsequent sessions were delivered by different nurses:
I think myself and S doing it together, we seem to work quite well at this point, but as we get more patients, I think both of us will feel confident enough to do it on our own.
Mechanisms of impact of sleep restriction therapy
We explored causal mechanisms, specifically how the delivered intervention produced change. We were interested in how participants interacted with nurses and responded to SRT and its effects. This was crucial to understanding how the intervention worked.
Self-motivation and effort
Nurses observed that self-motivated patients were more likely to continue with SRT at home and those who put in the effort were more likely to succeed.
The patients that have made it to the end of the study [end of intervention delivery] have taken it upon themselves to continue that process at home. I think it is because the patients that have made it through are self-motivated patients.
I did succeed in waking up at that 6 o’clock time, almost every time though; because I was so keen to see those results. I put the effort in, and the will power wasn’t too difficult.
Difficulty changing sleep habits
Some patients tried hard to adhere with their SRT but changing their existing sleep habit was challenging.
I used to do 12-hour shifts on a brain injury unit, so I used to come straight home at half eight, get a shower and go straight to bed, because I’d be up for 12 hours probably, the next day. So that’s carried on, now I’m retired, I still like to get into bed half past eight, read … and of course the lady has explained to me that I had to stay up till midnight, and I thought – I’m never going to be able to do this. And I tried my hardest, but that was very difficult for me actually.
Experiencing anticipated benefits
Most patients reported that the initial week could be hard but after that they started to feel the benefits, they felt more refreshed, their SE increased, and they were able to fall asleep more quickly and stay asleep.
I mean after you get over that initial first week, you start to feel the benefits of it. I mean physically it hasn’t helped, because my condition, there’s not a cure for, but mentally I’m so much better for it, and it’s worth sticking with and seeing it through.
[Sleep efficiency was] [a]bout 70% at the start, and the last sort of eight weeks or so, it has been around 85% mark; so that must be a good sign.
Patients noted they fell asleep more quickly than prior to SRT and so spent less time in bed awake. Nurses observed that patients receiving SRT perceived bedtime as a more positive experience and there were changes in perception of sleep:
Frequently could be anything up to an hour or an hour and a half previously, but now down to 15, 20, 25 minutes maximum, most nights before I drop off.
She wasn’t having a nap, it was becoming a positive thing because she was looking forward to going to bed; and knowing that when she went to bed, she’d sleep. And even if she woke up, she said, she might wake up once or twice in the night, but she was able to get straight back off to sleep again. So that was good.
Patients also noticed a change in their perception of sleep:
Even though I didn’t think my sleeping patterns had changed an awful lot, because of restriction, my perception of it had changed.
Continuing support for adverse effects
Patients did report some adverse effects during the initial phases of SRT.
But the second week and third week, I felt exhausted. Really exhausted, so. Then felt alright again this week.
I feel I could do with going to bed a bit earlier. I know in the booklet it suggests that you do things, but when you are so tired, you just can’t function.
Several patients and nurses highlighted the need for continued support following the end of the 4-week therapy.
The way it was expressed to me, and I certainly did, was to keep going, you know, and they had some spare sheets to fill out, and keep that diary going; and to be quite honest, it’s like anything: you start with good intentions, and then it slides off; so I think having more ongoing support over a longer period, probably would have helped me better, than it just coming to an end after 4 weeks.
Well for me anyway, 4 weeks wasn’t long enough for me at all … What’s the point? Nobody is going to see it (Sleep diary). And the first thing I did that day was have a nap – I’ve finished now, I can have a nap. So, I have reverted back to having naps now in the day. So, my insomnia at night has got worse.
They were a bit like – ‘Where do we go from now?’ … The chap I think was a little bit – ‘Oh!’; a little bit lost, if anything – ‘What do I do now?’; because he has not got anyone to report to at the end of the week. So just reassuring that he would get follow-up at 3 months, 6x months. So, it felt a little bit odd, if I am honest; that that’s it then and we are done.
I sort of did say to her, you know, don’t feel that we are abandoning you completely, there will be follow-ups, and if you’re at any stage really struggling and you want to have a chat about it, then come back to me.
Difficulties maintaining sleep restriction therapy
Patients expressed difficulties with very early rise times and the ability to maintain SRT every day.
Yeah. To do it overall, completely, yes, you know 365 days of the year. For me it is impractical, impossible.
My hardest bit was the getting up at the time she wanted me to get up; and I couldn’t do that. I was getting up way too early, way too early.
Reasons for withdrawal
Nurses shared opinions of why patients were likely to withdraw from the intervention, which was related to conflicting commitments, tiredness, negative attitudes (in particular, where other commitments were perceived to be impacted) and lack of self-efficacy.
The patients that are kind of like – Oh, yeah. And they go along. And it’s – Well I can’t do it on at Saturday because of this, and I can’t do this or that … or I’m not sure that will work. And I say – Well you know just try. This is your sleep efficiency now, and if we can improve on that, then anything above that number is an improvement, sort of thing. But sometimes when patients withdraw, you are not always surprised.
So, having the min of 5 hours in bed, and he just said – I can’t go to bed at 1 a.m. He just refused to do it. We talked about setting it back earlier … The first patient was younger, but she had very similar reasons in terms of she always went to bed at a set time.
That was the biggest complaint that he just felt far too tired and didn’t feel he could go about his daily routines and things because of the tiredness. And another lady, said she had been doing this for so many years, ‘I don’t think I can manage with how I am’.
Contextual factors in providing sleep restriction therapy in primary care
Contextual factors include those ‘external to the intervention that may act as a barrier or facilitator to its implementation or its effects’. Practice managers, GPs and nurses all commented on contextual factors, relating to the practicalities of delivery within practices and the facilitators and challenges of sustaining and scaling-up the intervention more widely.
Time constraints and conflicting priorities for nurses
Practice managers were aware that nurses had concerns about time constraints. These included the difficulties of fitting in extended SRT appointments into existing consultation times which were generally shorter. There were also concerns about pre-booking the appointments in advance, again due to lack of time.
The nurse practitioners who are doing the study, they are enjoying doing it, but they are worried about time constraints; and in particular trying to get those four appointments booked in on a weekly basis. And in general practice, that’s very difficult for us.
But it looks like yeah, nurses can deliver this, it is my perception, if they feel confident and competent to. The only question I’d guess I’d have is how long their appointment slots are because they are going to have to factor that into clinics and stuff. Because if they are set up for 10-minute slots then obviously they need more time than that.
Freeing-up general practitioner time
Sleep restriction therapy could free up GP time, because it was an intervention that might stop patients calling into the surgery for sleep medication or to discuss their sleep problems.
Actually, what your argument is, if this works, is that actually I think this is something that GPs would take on board quite readily because actually it’s taking work away from GPs and it’s giving an intervention that will actually free up time, I think, actually free up GP time. So if we can avoid patients phoning in for sleeping tablets, or coming to discuss sleep problems, and sort of following up these patients that goes on and on, if they’ve got an intervention they can do early on, then I think that’s something that GPs would think is a worthwhile thing to do.
Alternative delivery options
Practice staff felt it would be helpful to designate specific times and days for the SRT clinic to be held. This would help staff organise clinics, book patients for appointments and free time for nurses to complete additional administrative tasks associated with SRT delivery. One suggestion was to consider treating SRT like other behaviour-change clinics, including using set weekly times.
The way I see it running is, if we treat it like a behaviour change intervention, just like our weight management courses.
… even if we did it with our nurses, we really should have said – right, these are the days that we are going to offer it.
Several practice managers wondered about using other staff members such as healthcare assistants.
We have a very capable HCA, who would be more than capable of actually sitting and going through this with someone; and obviously that would be a lot more cost-effective.
Small group therapy sessions were also suggested as a means of delivery and a way of optimising nurse time.
If they saw maybe four or five in a group; not to make it too big a group; because then you can’t personalise it, so much. I think it probably be good for the individual patients as well because as a group meeting for that education and going through it, there’s like a bit of a support group there for them as well.
CRN
Don’t know. But for me I think a group environment with a nurse would have been just as effective as the one to one.
Patient: AF57
Practice staff, including GPs, were supportive, but they did have some reservations about time constraints, availability and having set days for clinics. To ensure the intervention could be delivered in routine general practice suggestions were made that SRT is delivered in the format of other behavioural interventions (e.g. smoking cessation and weight-management courses).
Quantitative results and joint display
Most patients interviewed either had an improvement or at least no deterioration in SE. Table 32 displays baseline ISI and SE, and weekly SE during the intervention nurse session together with summary extracts from any notes made by the nurses during the SRT sessions and a ‘representative’ quote from each patient regarding the SRT process. This indicated, not unexpectedly, that participants who found SRT a positive process showed improvements in SE, while those who struggled with SRT did not.
Discussion
The aim of the process evaluation was to establish the experiences and perceptions of patients, nurses, and GPs or practice managers of SRT as part of the HABIT trial and to investigate how SRT was received and delivered, understand why it worked or did not, and explore facilitators or barriers to implementation that may affect wider use of this treatment in primary care, should the intervention prove effective.
Both patients and nurses reported that they were able to quickly grasp the purpose of SRT and the related processes. Patients preferred face-to-face consultations and felt that these helped maintain motivation. Although face-to-face interactions have been found to be preferred in some studies, overall the evidence is lacking that therapeutic alliance, disclosure, empathy, attentiveness or participation differs in face-to-face compared with telephone delivery of psychological interventions.68 Some patients found calculating SE difficult and felt that they needed help from the nurse, while nurses pointed out that helping someone with maths over the telephone was harder than in person.
All patients interviewed found the first week of therapy difficult, with reduced time in bed and strict bedtime and rising times. This is consistent with previous evaluations of SRT, where participants reported worsening of daytime functioning in the first week, with improvements felt after a period of adjustment.69,70 Additionally, it has been found that restriction of time in bed, which leads to transient daytime sleepiness and related side effects, outperforms regular bed and rise times without restriction.25,26 This suggests that while the initial increase in side effects is challenging it may also be a necessary part of the therapy.
In this study there was negotiation between the nurses and the patients regarding sleep times and the need for flexibility, which was supported to some extent by the protocol.1 Changing ingrained behaviours, in this case fixed night-time (or daytime nap) routines, was challenging and the flexibility on the part of the nurses allowed patients to feel some level of control. The flexibility built into the protocol meant that these did not affect the fidelity of delivery. Fidelity was found to be high by the independent reviewer. One nurse interviewed did mention sharing delivery of the intervention with a colleague for one patient, which would only be problematic if inconsistent advice was given.
Participants reported adverse effects such as increased tiredness, ‘exhaustion’ and worries about driving, which have been found in other studies.69,70 For some, these experiences led them to discontinue SRT (Table 8). Other reported confounding factors, external to the intervention, included sleep disturbance due to menopause symptoms and the use of sleep aids (such as sedatives) which extended the allocated sleep time. These factors should be considered in the future rollout of SRT.
Patients who experienced improved SE also reported concerns, most commonly that 4 weeks of SRT was not long enough. All participants found the first week of the intervention very difficult as their body adjusted to limited time in bed. By the third week some were seeing significant benefits. For example, one participant spoke of being woken by their alarm for the first time in years. Others only started to see benefits by the final week and as such felt the loss of support at the end of the intervention had a direct impact on their motivation to continue. Those who saw improvements earlier tended to be more likely to continue after the final therapy session, while those that felt the benefit later were more likely to revert to previous habits. One patient reported taking a nap in the afternoon the day after the final session and that they quickly reverted to their previous habits as there was no-one ‘watching over them’ any more. This is reflected in the joint display (see Table 32), where comparisons between recorded improvements in sleep and the qualitative data suggest that participants who felt they were better able to apply the SRT intervention showed more improvement than those who struggled or needed more time and support. This is a significant finding that indicates the importance of individual/personalised delivery with regular check-ins continuing for some until the new habits and sleep patterns have been reinforced.
Previous research suggested it was possible for a single GP to deliver a modified version of SRT in general practice to patients without comorbidity,28 and this study confirmed that it was possible for nurses to deliver the intervention in a consistent manner across multiple practices. Practice managers and GPs also agreed that the intervention could be successfully delivered by nurses in this setting, which they considered may free up time for GPs. Several suggestions were put forward regarding how the intervention could be rolled out more widely. Practice managers suggested setting up specific clinics at set times in the week that could be run by healthcare assistants rather than practice nurses. It was also suggested that sessions could be run in small groups in a similar way to other behaviour-change clinics such as smoking cessation or weight-loss clinics. This is something that could be further explored in subsequent research.
Limitations
A limitation of this study was that we did not interview participants who withdrew or did not start the intervention. Reasons for withdrawal from intervention were systematically recorded as part of the trial, indicating that a key reason for discontinuation was finding the intervention too challenging, with respect to both adherence and the acute effects of restricted sleep opportunity. This type of behavioural therapy may not suit every patient, but a better understanding of why people discontinued SRT might inform changes to the intervention and ongoing support, leading to better retention. This is reflected by findings of this study where those who found the intervention hard, or did not see benefits until later, were less likely to maintain SRT and more quickly reverted to previous sleep habits.
Conclusions
We found that SRT can be successfully delivered by nurses in general practice and was generally well received by patients. Ongoing support after the initial intervention period could be assessed to determine whether this leads to improved adherence.