A protocol for the systematic review and meta-analysis of clinical trials of interventions to improve sleep in people with mild cognitive impairment or dementia.

Patrick Crowley; Evelyn Flanagan; Rónán O'Caoimh

doi:10.12688/hrbopenres.13988.1

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Study Protocol

A protocol for the systematic review and meta-analysis of clinical trials of interventions to improve sleep in people with mild cognitive impairment or dementia.

[version 1; peer review: 1 approved with reservations]

Patrick Crowley ^1,2, Evelyn Flanagan^1,2, Rónán O'Caoimh¹

PUBLISHED 07 Oct 2024

Author details Author details

¹ Mercy University Hospital, Cork, County Cork, T12 WE28, Ireland
² University College Cork, Cork, County Cork, Ireland

Patrick Crowley
Roles: Conceptualization, Data Curation, Funding Acquisition, Project Administration, Writing – Original Draft Preparation

Evelyn Flanagan
Roles: Funding Acquisition, Writing – Review & Editing

Rónán O'Caoimh
Roles: Conceptualization, Funding Acquisition, Project Administration, Supervision, Writing – Review & Editing

OPEN PEER REVIEW

REVIEWER STATUS

Abstract

Background

While sleep disturbance is common in advanced dementia, leading to negative outcomes, there is growing evidence that sleep disturbance begins early in prodromal dementia and may contribute to cognitive decline. Sleep is therefore an important treatment target throughout the natural history of dementia.

The existing literature regarding interventions for sleep in people with cognitive impairment is beset by wide heterogeneity in the sleep measurement tools used and outcome measures reported, which limits data synthesis and impedes the development of a robust evidence base for these interventions.

Aim

We propose to undertake a systematic review and meta-analysis to assess the evidence base from clinical trials for both pharmacological and non-pharmacological interventions to improve sleep in people with cognitive impairment. We will also extract data regarding the sleep measurement tools and outcome measures used in these studies to underpin the development of a core outcome set for future clinical trials in the area.

Methods

This systematic review and meta-analysis will include randomised and non-randomised controlled clinical trials that assess interventions to improve sleep in participants with mild cognitive impairment or dementia. Medline, CINAHL, PsycINFO, and the Cochrane CENTRAL database will be searched from inception to present. A flow chart will illustrate the study selection process in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines.

The methodological quality and risk of bias of included studies will be assessed. Heterogeneity will be tested. A narrative synthesis will be undertaken where meta-analysis is not feasible.

Conclusion

This systematic review and meta-analysis will help inform clinical practice by evaluating the available evidence for interventions to improve sleep in people with mild cognitive impairment or dementia. It will also facilitate the development of a core outcome set that will improve the coherence and utility of data emerging from future clinical trials.

Keywords

Sleep. Dementia. Mild cognitive impairment. Systematic Review. Meta-analysis. Protocol.

Corresponding author: Patrick Crowley

Competing interests: No competing interests were disclosed.

Grant information: This systematic review is undertaken as part of a project that is funded by a grant from Dementia Trials Ireland, Health Research Board Clinical Trial Network, under grant number: HRB DTICTN-2021-003. The funder did not influence the preparation of this protocol.
The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Copyright: © 2024 Crowley P et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

How to cite: Crowley P, Flanagan E and O'Caoimh R. A protocol for the systematic review and meta-analysis of clinical trials of interventions to improve sleep in people with mild cognitive impairment or dementia. [version 1; peer review: 1 approved with reservations]. HRB Open Res 2024, 7:63 (https://doi.org/10.12688/hrbopenres.13988.1) First published: 07 Oct 2024, 7:63 (https://doi.org/10.12688/hrbopenres.13988.1) Latest published: 07 Oct 2024, 7:63 (https://doi.org/10.12688/hrbopenres.13988.1)

Introduction

Sleep is important for good physical and mental health¹. Sleep patterns change as people get older², however, with significant declines identified in Non-Rapid Eye Movement (NREM) slow wave sleep and sleep efficiency³. The prevalence of such sleep disturbance is even greater among older people with cognitive impairment⁴, and its prevalence continues to increase as cognitive impairment advances⁵.

While the association between sleep disturbance and cognitive impairment is well established⁶, the relationship has not always been clear. While sleep disturbance was previously presumed to be a symptom of cognitive impairment⁷, the relationship appears to be more complex with studies now suggesting that it may be both causal and bi-directional⁸.

There is, for example, plausible evidence that sleep disturbance plays a role in precipitating or accelerating deposition of the beta-amyloid and tau proteins that are characteristic of the pathophysiology of Alzheimer’s Disease (AD)⁹. Cerebrospinal fluid levels of beta-amyloid fluctuate diurnally, rising during wakefulness before declining during sleep¹⁰. The glymphatic system that clears toxic metabolic waste products from the brain is more efficient during sleep¹¹. Sleep deprivation has been shown to increase accumulation and cortical deposition of both beta-amyloid¹² and tau¹³. A recent meta-analysis suggests that up to 15% of cases of AD could be attributable to sleep disturbance¹⁴.

Although the recently published Dementia Prevention, Intervention and Care: 2024 report of the Lancet Commission¹⁵ has reaffirmed that additional research is needed to clarify the effect of sleep on cognitive decline, interest is nevertheless growing in sleep as a modifiable risk factor that may be a target for preventative intervention in mild cognitive impairment (MCI) or prodromal dementia¹⁶.

Improving sleep remains an important treatment target for patients with more advanced dementia. Regardless of the underlying reason, sleep disturbance tends to worsen with advancing dementia¹⁷, leading to strained relationships with caregivers who experience considerable physical and emotional distress and burnout as a consequence¹⁸. The increased carer burden caused by sleep disturbance in people with dementia has been shown to lead to sub-optimal care¹⁹ and early institutionalisation²⁰.

A 2014 Cochrane review of pharmacological interventions for sleep in people with AD²¹ included only five studies, illustrating the dearth of research data to guide clinical decisions among this cohort. The review found that, although it had a favourable side-effect profile, melatonin did not have any positive benefit on sleep parameters. The atypical anti-depressant, trazadone, did result in significantly improved nocturnal total sleep time (NTST) and sleep efficiency, with no appreciable effect on daytime sleep or cognition. A 2020 Cochrane review of pharmacotherapies in dementia²² included nine studies, including two additional studies involving orexin antagonists that provided moderate certainty evidence of improved NTST and wakefulness after sleep onset. A more recent systematic review from 2024 involving participants with AD²³ included 14 studies. Trazadone again demonstrated positive effects in treating insomnia in people with AD, with several studies also indicating a noticeable improvement in cognition. The sedative-hypnotic, eszopiclone, and orexin antagonists were both found to improve sleep efficiency and total sleep time, while melatonin did not. Although zopiclone, another sedative-hypnotic medication, improved NTST and the number of night-time awakenings, it exhibited a worrisome side-effect profile with risk of increased confusion, agitation and hallucinations. Each of the aforementioned reviews were limited by the small sample sizes in the included studies. The latter review concluded by saying “the research landscape surrounding sleep disturbances in people with AD is characterised by a conspicuous gap in knowledge and notable challenges in establishing a consensus regarding the most effective and safest pharmacological intervention”.

A 2019 systematic review and meta-analysis of non-pharmacological interventions to improve sleep in people with cognitive impairment²⁴ found modest improvements in sleep efficiency with bright light therapy (BLT) and multi-domain interventions, usually incorporating BLT, but only when all data were pooled. Data were small in number, however, mainly involving residents in institutional care and few data were available for the effectiveness of these interventions in people with MCI. Further, most of the small number (n=3) of randomised controlled trials included in the meta-analysis showed unclear risk of bias. A 2023 Cochrane review of non-pharmacological treatments for sleep in people with dementia²⁵ included 19 studies, 14 of which were conducted in nursing homes. It concluded with low certainty that physical and social activity interventions may improve NTST and sleep efficiency, while multi-modal interventions may improve NTST. The effects of BLT were uncertain, with conflicting results in the included studies.

A common thread running throughout reviews of both pharmacological and non-pharmacological interventions to improve sleep in people with cognitive impairment is the wide variety in research methodology, particularly in relation to the outcome measures employed^21–26. This heterogeneity limits the comparability of data from different studies and impedes the development of a reliable evidence base to guide clinical practice.

Given the importance of sleep as a treatment target throughout the natural history of dementia, to potentially slow progression of early-stage disease and to reduce symptom burden in more advanced cases, we propose to undertake an updated systematic review and meta-analysis of clinical trials involving both pharmacological and non-pharmacological interventions to improve sleep in people with MCI or dementia. This will clarify the evidence currently available to support clinical treatment decisions. Furthermore, we will collate data regarding the sleep measurement tools used and the sleep outcome measures reported in included trials. This will inform the development of a core outcome set that will improve the coherence and comparability of data emerging from future clinical trials.

Review question

This protocol for a systematic review and meta-analysis will answer the following question: “What is the evidence from randomised and non-randomised clinical trials to support interventions that aim to improve sleep in people with MCI or dementia?”

The PICO Framework²⁷ will be employed to examine randomised and non-randomised clinical trials among participants with MCI or dementia that assessed pharmacological and non-pharmacological interventions designed to improve sleep by comparing the studied intervention to at least one other intervention/non-intervention/placebo control group in which the goal of improving sleep was the desired outcome. (Table 1).

Table 1. PICO Framework.

MCI = Mild cognitive impairment.

Participants	People with MCI or dementia
Intervention	Any pharmacological or non-pharmacological intervention to improve sleep
Comparator/ control	A distinct control group that is exposed to either: • Placebo • A different intervention • A non-intervention
Outcome	Improved sleep

Methods

The Preferred Reporting Items for Systematic Review and Meta-Analyses - Protocols (PRISMA-P) guidelines²⁸ were followed in producing this protocol (see completed PRISMA-P checklist in Table 2 [see Extended Data]). The protocol has been registered on the International Prospective Register of Systematic Reviews (PROSPERO), registration number: CRD42024556750.

Eligibility criteria

This systematic review and meta-analysis will include randomised and non-randomised controlled clinical trials that assess pharmacological and non-pharmacological interventions to improve sleep in people with MCI or dementia.

Inclusion criteria

original peer reviewed articles
written in the English language
reporting on clinical trials of interventions to improve sleep, involving:
- participants:
  - ■ aged ≥18 years.
  - ■ at least 80% of whom have a stated diagnosis of MCI or dementia or, if no such diagnosis is stated, at least 80% of whom score within the generally accepted threshold for cognitive impairment on standard neurocognitive testing or, if said percentage is impossible to calculate based on the information available, the standard deviation/interquartile range of scores on standard neurocognitive testing is within the generally accepted threshold for cognitive impairment. Trials will also be included if a distinct sub-group of participants, for whom results are separately reported, meets this inclusion criterion.
- comparison of the studied intervention with at least one other intervention/non-intervention/placebo control group. While cross-over trials will be included, within-subjects trials that consecutively compare the studied intervention with another intervention or control within the same cohort of participants will not be included.
- at least one primary or secondary outcome relating to sleep. Trials that use composite assessments involving sleep as outcome measures will be included only if the sleep component of the assessment is separately reported. For example, trials that utilise the Neuropsychiatric Inventory (NPI)²⁹, a measure of non-cognitive symptoms in dementia, as an outcome measure will be included only if the score pertaining specifically to the sleep domain of the NPI is reported.

Exclusion criteria

Studies primarily involving participants who are:
- post-stroke
- post traumatic brain injury
- in-patients in intensive care units
- oncology patients
Abstracts/conference proceedings, book chapters, grey literature.

Search strategy

The following databases will be searched from inception to date: Medline (Ovid), CINAHL, PsycINFO, and the Cochrane CENTRAL database. The search strategy for each database is detailed separately in Tables 3a–3d (see Extended Data). The interTASC Information Specialists Sub-Group (ISSG) Search Filter Resource was used to filter for clinical trials³⁰. Given the high prevalence of cognitive impairment among nursing home residents^31,32, it was felt prudent to include ‘nursing home resident’ (and synonymous terms) with cognitive impairment (and synonymous terms) in order to ensure capture of trials conducted in nursing homes that did not explicitly reference participants’ cognitive diagnoses but may nevertheless meet our inclusion criteria by reporting cognitive assessment scores. To illustrate this point, in a 2018 systematic review of non-pharmacological interventions to improve night-time sleep among residents of long-term care settings³³, over half of included studies involved participants with dementia but this was not always explicitly stated in the studies themselves³⁴. The search strategy was reviewed in accordance with the Peer Review of Electronic Search Strategies (PRESS) Guideline Statement³⁵. Table 4 illustrates the predicted outcome for this search strategy (see Extended Data).

Study selection

Search results will be merged using reference management software and duplicate records will be removed. Remaining titles will be reviewed to remove articles that are obviously irrelevant. Abstracts of retained articles will then be examined against eligibility criteria and those that are obviously irrelevant will be removed. Finally, the full text of remaining articles will be reviewed independently by two separate reviewers to determine which articles comply with eligibility criteria. Any disagreements regarding inclusion of articles will be resolved by discussion and consensus agreement, where possible, or by independent review by the project supervisor (ROC), where necessary.

Data extraction

Data will be extracted from the included articles using standardised forms that will facilitate recording of the data set out in Table 5 (see Extended Data).

Quality assessment

Methodological quality of included studies will be assessed using the Joanna Briggs Institute Checklist for Quasi-Experimental and Randomised Controlled Trials³⁶. Risk of bias will be assessed using the Cochrane Collaboration’s Tool for Assessing Risk of Bias³⁷.

Data synthesis and analysis

Heterogeneity will be tested using Higgins’ I² statistic³⁸. It is expected that there will be substantial heterogeneity both in the tools used to measure sleep and in the outcome measures reported²⁶. Meta-analyses will be undertaken, where possible, if appropriate conditions are met in certain subgroups. Quantitative data will, where possible, be pooled in statistical meta-analysis to perform data synthesis. The significance threshold will be p<0.05 on two sides. A forest plot for each parameter will be constructed to indicate the weight ratio of each incorporated trial. Where meta-analysis is not feasible, a narrative synthesis will be undertaken focussing on population characteristics and the performance of interventions compared to controls.

Potential limitations

Based on the results of previous systematic reviews and meta-analyses^21–26, there is likely to be high levels of heterogeneity in sleep measurement tools used and sleep outcome measures reported, which will limit the scope for meta-analysis. Furthermore, studies involving participants with cognitive impairment are prone to inaccuracies if data collection is reliant on subjectively reported outcome measures. Limiting the scope of this study to four databases may result in some relevant articles being missed, although these are commonly accessed for studies examining sleep based on previous similar studies²⁴.

Discussion

Despite the need for further evidence to clarify the relationship between sleep disturbance and cognitive impairment¹⁵, there is growing interest in the possibility that improving sleep in the early prodromal stages of dementia may help prevent or delay cognitive decline¹⁶. Sleep disturbance is common at all stages of established dementia^5,17, leading to negative outcomes for patients^19,20 and their caregivers¹⁸.

Previous systematic reviews and meta-analyses have been piecemeal, either focussed entirely on pharmacological²² or non-pharmacological²⁴ interventions, or have been restricted to specific causes²³ or stages²⁶ of dementia. Furthermore, all of these reviews have illustrated a relative dearth of existing research and have been limited by high levels of heterogeneity impeding data synthesis and the derivation of a reliable evidence base to guide clinical practice. The treatment of sleep in people with cognitive impairment is a dynamic area of increasing research interest, with growing evidence supporting its role, so it is important to update the aforementioned reviews with one review encompassing both pharmacological and non-pharmacological interventions to improve sleep throughout the spectrum of cognitive decline from MCI to dementia. This updated study will help chart the topography of the current research landscape, thus clarifying the existing evidence base and helping to identify gaps in the current knowledge that need to be bridged by future research.

Given the apparent paucity of relevant research heretofore, and the challenges inherent in conducting research among people with cognitive impairment³⁹, it is important to ensure that future research is coherent so that its utility can be maximised. An ancillary objective of this review, therefore, will be to identify the sleep measurement tools used and the outcome measures reported in included trials so as to inform the development of a core outcome set that will guide the conduct of future clinical trials.

Conclusion

The planned systematic review and meta-analysis outlined in this protocol will help inform clinical practice by evaluating the available evidence for both pharmacological and non-pharmacological interventions to improve sleep in people with MCI and dementia. Additionally, the review will contribute to the development of a core outcome set for future clinical trials involving interventions to improve sleep in people with cognitive impairment, thus improving the coherence and utility of data emerging from those trials.

Ethics & dissemination

This systematic review and meta-analysis does not require ethical approval due to absence of human participants. Results of the systematic review will be published in a peer-reviewed journal and presented at relevant academic conferences.

Data availability

Underlying data

No data are associated with this article.

Extended data

Open Science Framework: A protocol for the systematic review and meta-analysis of clinical trials of interventions to improve sleep in people with mild cognitive impairment or dementia. https://doi.org/10.17605/OSF.IO/HXTYW

This article contains the following extended data⁴⁰:

Tables 3a-d (Search strategies for Medline, the Cochrane CENTRAL database, CINAHL, and PsycINFO).

Table 4 (Search Strategy Predicted Outcome)

Table 5 (Data Extraction Form)

Reporting guidelines

Open Science Framework: A protocol for the systematic review and meta-analysis of clinical trials of interventions to improve sleep in people with mild cognitive impairment or dementia. https://doi.org/10.17605/OSF.IO/HXTYW

This article contains the following reporting guidelines⁴⁰:

Table 2 (Completed PRISMA-P Checklist)

PRISMA Flowchart

Data are available under the terms of the Creative Commons Zero "No rights reserved" data waiver (CC0 1.0 Public domain dedication).

Faculty Opinions recommended

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Author details Author details

¹ Mercy University Hospital, Cork, County Cork, T12 WE28, Ireland
² University College Cork, Cork, County Cork, Ireland

Patrick Crowley
Roles: Conceptualization, Data Curation, Funding Acquisition, Project Administration, Writing – Original Draft Preparation

Evelyn Flanagan
Roles: Funding Acquisition, Writing – Review & Editing

Rónán O'Caoimh
Roles: Conceptualization, Funding Acquisition, Project Administration, Supervision, Writing – Review & Editing

Competing interests

No competing interests were disclosed.

Grant information

This systematic review is undertaken as part of a project that is funded by a grant from Dementia Trials Ireland, Health Research Board Clinical Trial Network, under grant number: HRB DTICTN-2021-003. The funder did not influence the preparation of this protocol.
The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

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Published: 07 Oct 2024, 7:63

https://doi.org/10.12688/hrbopenres.13988.1

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© 2024 Crowley P et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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Crowley P, Flanagan E and O'Caoimh R. A protocol for the systematic review and meta-analysis of clinical trials of interventions to improve sleep in people with mild cognitive impairment or dementia. [version 1; peer review: 1 approved with reservations]. HRB Open Res 2024, 7:63 (https://doi.org/10.12688/hrbopenres.13988.1)

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Reviewer Report 14 Nov 2024

Rosemary Gibson, Massey University, Palmerston North, New Zealand

Approved with Reservations

https://doi.org/10.21956/hrbopenres.15353.r42673

Thank you for the opportunity to review this paper – “A protocol for the systematic review and meta-analysis of clinical trials of interventions to improve sleep in people with mild cognitive impairment or dementia.” For consideration in HRB Open Research.
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Thank you for the opportunity to review this paper – “A protocol for the systematic review and meta-analysis of clinical trials of interventions to improve sleep in people with mild cognitive impairment or dementia.” For consideration in HRB Open Research.

This is a protocol study for a systematic review and meta (or narrative) analysis in an important area of research.

The introduction provides a strong rationale for work in this field – including justifying how changes and disturbances to sleep can contribute or exacerbate cognitive decline, as well as the complexities and bidirectional nature of sleep’s relationship with cognitive and mental health.

In this introduction – pre-existing recent systematic reviews are referred to with regards to pharmacological and non-pharmacological interventions for sleep disturbances in dementia. These conclude that gaps in knowledge etc remain and that previous studies are small and heterogeneous etc. (perhaps this quote needs a page citation?)
However, I am not sure how conducting another review will attend to this gap – as opposed to conducting more comprehensive and conclusive trials..? Recommend making it clearer in aims etc around the idea of a broader and more comprehensive review required to have it all info one place (and updated).

It seems the review proposed is intended to be more detailed than the past ones. However, the inclusion of both pharmacological and non-pharmacological trials among people with ranges of types and stages of dementia as well as in and out of nursing homes – so I imagine this will also yield studies with very mixed sample sizes, types of populations, and methods producing another set of mixed and inconclusive results . So, I recommend making it clearer how the proposed review will be unique compared to previous ones. These issues are noted as potential limitations in the discussion – so, again, how will this differ from other such reviews and why do we need another one?

The methods for searching literature and inclusion and exclusion is clearly laid out – as is the synthesis and analysis of the final data set so this inspires the reader to be excited to see the findings.

Finally – while this is well written and an exciting idea, I am not sure if we need a separate protocol paper for a proposed systematic review rather than the actual review itself. I would prefer to see the complete study and recommend publishing this protocol alongside the review results.

Is the rationale for, and objectives of, the study clearly described?

Partly
Is the study design appropriate for the research question?

Partly
Are sufficient details of the methods provided to allow replication by others?

Yes
Are the datasets clearly presented in a useable and accessible format?

Not applicable

Competing Interests: No competing interests were disclosed.

Reviewer Expertise: Sleep with ageing, dementia, caregiving

I confirm that I have read this submission and believe that I have an appropriate level of expertise to confirm that it is of an acceptable scientific standard, however I have significant reservations, as outlined above.

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Rosemary Gibson, Massey University, Palmerston North, New Zealand

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Reviewer Report

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14 Nov 2024 | for Version 1

Rosemary Gibson, Massey University, Palmerston North, New Zealand

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Approved With Reservations

Thank you for the opportunity to review this paper – “A protocol for the systematic review and meta-analysis of clinical trials of interventions to improve sleep in people with mild cognitive impairment or dementia.” For consideration in HRB Open Research.

This is a protocol study for a systematic review and meta (or narrative) analysis in an important area of research.

The introduction provides a strong rationale for work in this field – including justifying how changes and disturbances to sleep can contribute or exacerbate cognitive decline, as well as the complexities and bidirectional nature of sleep’s relationship with cognitive and mental health.

In this introduction – pre-existing recent systematic reviews are referred to with regards to pharmacological and non-pharmacological interventions for sleep disturbances in dementia. These conclude that gaps in knowledge etc remain and that previous studies are small and heterogeneous etc. (perhaps this quote needs a page citation?)
However, I am not sure how conducting another review will attend to this gap – as opposed to conducting more comprehensive and conclusive trials..? Recommend making it clearer in aims etc around the idea of a broader and more comprehensive review required to have it all info one place (and updated).

It seems the review proposed is intended to be more detailed than the past ones. However, the inclusion of both pharmacological and non-pharmacological trials among people with ranges of types and stages of dementia as well as in and out of nursing homes – so I imagine this will also yield studies with very mixed sample sizes, types of populations, and methods producing another set of mixed and inconclusive results . So, I recommend making it clearer how the proposed review will be unique compared to previous ones. These issues are noted as potential limitations in the discussion – so, again, how will this differ from other such reviews and why do we need another one?

The methods for searching literature and inclusion and exclusion is clearly laid out – as is the synthesis and analysis of the final data set so this inspires the reader to be excited to see the findings.

Finally – while this is well written and an exciting idea, I am not sure if we need a separate protocol paper for a proposed systematic review rather than the actual review itself. I would prefer to see the complete study and recommend publishing this protocol alongside the review results.

Is the rationale for, and objectives of, the study clearly described?

Partly
Is the study design appropriate for the research question?

Partly
Are sufficient details of the methods provided to allow replication by others?

Yes
Are the datasets clearly presented in a useable and accessible format?

Not applicable

Competing Interests

No competing interests were disclosed.

Reviewer Expertise

Sleep with ageing, dementia, caregiving

I confirm that I have read this submission and believe that I have an appropriate level of expertise to confirm that it is of an acceptable scientific standard, however I have significant reservations, as outlined above.

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A protocol for the systematic review and meta-analysis of clinical trials of interventions to improve sleep in people with mild cognitive impairment or dementia.

Abstract

Background

Aim

Methods

Conclusion

Keywords

Introduction

Review question

Table 1. PICO Framework.

Methods

Eligibility criteria

Search strategy

Study selection

Data extraction

Quality assessment

Data synthesis and analysis

Potential limitations

Discussion

Conclusion

Ethics & dissemination

Data availability

Underlying data

Extended data

Reporting guidelines

References

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A protocol for the systematic review and meta-analysis of clinical trials of interventions to improve sleep in people with mild cognitive impairment or dementia.

Abstract

Background

Aim

Methods

Conclusion

Keywords

Introduction

Review question

Table 1. PICO Framework.

Methods

Eligibility criteria

Search strategy

Study selection

Data extraction

Quality assessment

Data synthesis and analysis

Potential limitations

Discussion

Conclusion

Ethics & dissemination

Data availability

Underlying data

Extended data

Reporting guidelines

References

Comments on this article Comments (0)

Open Peer Review

Comments on this article Comments (0)

Open Peer Review

Reviewer Status

Reviewer Reports

Comments on this article

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Are you a HRB-funded researcher?

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