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Study Protocol

Effectiveness of non-pharmacological falls prevention interventions for people with Multiple Sclerosis, Parkinson’s Disease and stroke: protocol for an umbrella review

[version 1; peer review: 3 approved with reservations]
PUBLISHED 24 Apr 2020
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Abstract

Background: Falls are common among people with neurological diseases and are associated with many negative physical, psychosocial and economic consequences. Implementation of single diagnosis falls prevention interventions is currently problematic due to lack of participants and resources. Given the similarities in falls risk factors across stroke, Parkinson’s Disease (PD) and Multiple Sclerosis (MS), the development of an intervention designed for mixed neurological populations seems plausible and may provide a solution to current implementation challenges. This umbrella review aims to summarise the totality of evidence regarding the effectiveness of non-pharmacological falls prevention interventions for people with MS, PD and stroke and to identify the commonalities and differences between interventions that are effective for each disease to inform the development of an intervention for mixed diagnoses.
Methods: This umbrella review will be conducted and reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Electronic databases and grey literature will be searched. Systematic reviews of randomised controlled trials (RCTS) and studies investigating the effects of non-pharmacological falls prevention interventions on falls outcomes among people with MS, PD and stroke will be included. Methodological quality of included reviews will be assessed using the Assessment of Multiple Systematic Reviews 2 tool. The Grading of Recommendations Assessments, Development and Evaluation framework will be used to rate the quality of evidence. A summary of evidence table and narrative synthesis will be utilised to clearly indicate the findings.
Discussion: This umbrella review presents a novel and timely approach to synthesise existing falls literature to identify effective non-pharmacological interventions for people with MS, PD and stroke. Of importance, this umbrella review will use a robust methodology to explore the key differences and similarities in effective interventions for individuals with these neurological diseases to facilitate the development of an intervention for mixed neurological groups.

Keywords

Multiple Sclerosis, Parkinson’s Disease, Stroke, Falls, Intervention, Umbrella Review

Introduction

Fall rates are high among people with neurological diseases and are often associated with many negative consequences. Therefore, the development of effective falls prevention interventions for this cohort of individuals is a research priority. Up to 73% of stroke survivors experience a fall in the first year post-stroke1 and as many as 56% of people with Multiple Sclerosis (MS) fall in any given three-month period2. Similarly, 59% of people with Parkinson’s Disease (PD) report having at least one fall over a six-month period3. Physical injuries are a common consequence of a fall among people with neurological diseases with between 11–17% of falls resulting in injury46 but notably, this figure has been as high as 72% among stroke survivors7. Falls also have a number of psychosocial impacts including fear of falling and reduced self-efficacy8,9, leading to decreased independence, reduced social participation and diminished health-related quality of life9,10. Additionally, falls result in increased acute healthcare utilisation, higher home-care needs and/or greater institutional care needs57,11. This high rate of falls and range of associated physical, social and economic consequences highlights the need for an effective falls prevention intervention.

Recently there has been an increase in the number of interventions developed and evaluated for falls prevention among individuals with one specific neurological disease. This condition-specific approach to intervention is reflected in clinical practice where provision of services is typically disease-specific12. However, implementation of these interventions in the community is a challenge as finding sufficient numbers and resources to run single diagnosis groups is problematic for clinicians13. The National Strategy & Policy for the Provision of Neuro-Rehabilitation Services in Ireland has demonstrated the current deficits in services available to people with neurological diseases and the associated negative consequences at both the individual and system level12. This implementation strategy highlights the need for high-quality, person-centred care and timely access to services for people with neurological diseases to optimise outcomes12. One potential solution to this is the development of interventions that can be applied to mixed neurological populations rather than a group with one specific disease. Little is currently known about the feasibility or effectiveness of adopting this mixed population approach to falls rehabilitation with a scoping literature search revealing only one study examining the effect of a falls prevention intervention for people with MS, PD and stroke14. However, people with these neurological diseases share many common symptoms1520 and risk factors for falls, such as mobility impairments, reduced balance and cognitive deficits2123, and therefore, given these similarities, it is likely that programmes for mixed neurological groups are feasible. A mixed population approach to the development and provision of interventions has the potential to increase the number of eligible participants, reduce strain on healthcare resources and increase the number of services available to community-dwelling individuals living with neurological conditions, thereby meeting the rehabilitation needs of these individuals while simultaneously negating the negative effects associated with insufficient service provision. Therefore, the development of an intervention for individuals with mixed neurological diseases is timely to address the current implementation and service provision challenges in the community.

Following the Medical Research Council’s Framework, the first step in developing a complex intervention is the collation of the existing evidence-base24. Therefore, to develop an intervention that is implementable across diagnoses, it is necessary to first identify what elements of existing programmes are effective for each condition. A recent umbrella review was the first of its kind to investigate the effectiveness of exercise-only interventions at reducing falls for people with neurological diseases25. This study concluded that exercise interventions were effective at reducing falls for people with PD, but had insufficient evidence regarding their effectiveness for people with stroke or MS25. Falls are widely accepted as multifactorial, with a combination of physiological, behavioural, environmental and socioeconomic factors believed to influence falls risk26,27 and a limitation of that review is the consideration of exercise interventions only. Given the broad range of falls risk factors among people with neurological diseases4,2123,28,29, it can be hypothesised that a multifaceted intervention will result in a greater improvement in falls outcomes than one single-arm intervention delivered in isolation. Consequently, a multimodal approach to falls prevention that targets a number of these risk factors simultaneously appears intuitive and has been suggested to address modifiable falls risk factors23. Therefore, to develop an intervention that addresses the multifactorial nature of falls, there is a need to review the effectiveness of all non-pharmacological interventions across stroke, PD and MS. This umbrella review is novel in that it will use a robust methodology to assess the effectiveness of all non-pharmacological interventions, taking into consideration the multifactorial nature of falls. Additionally, this umbrella review will be the first of its kind to compare and contrast the effectiveness of interventions across diseases to facilitate the development of mixed neurological group interventions.

The objectives of this umbrella review are:

  • 1. To summarise the totality of evidence regarding the effectiveness of non-pharmacological falls prevention interventions for people with MS, PD and stroke.

  • 2. To identify commonalities and differences between interventions that are effective at reducing falls for people with MS, PD and stroke to inform the development of an intervention for mixed neurological groups.

Methods

Protocol and registration

An umbrella review will be conducted to identify systematic reviews (with or without meta-analysis) of studies investigating the effectiveness of non-pharmacological interventions to prevent falls among people with neurological diseases. In line with recommendations to improve transparency and reduce bias, this protocol was developed to outline the key objectives of this umbrella review and what methodology will be employed30. This protocol was designed using the guidance of the relevant items of the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocols (PRISMA-P) statement31, with reference to the Joanna Briggs Institute (JBI) Reviewer’s Manual32 and the PRISMA guidelines33,34. The PRISMA-P was developed to facilitate the design of protocols for systematic reviews, however, the relevant sections of the checklist will be used for this protocol in the absence of specific guidelines for the conduction and reporting of umbrella reviews35. The protocol was registered with the International Prospective Register of Systematic Reviews, PROSPERO, on 19th March 2020.

Search strategy

The following electronic databases will be searched to identify potentially relevant reviews: The Cochrane Database of Systematic Reviews, Joanna Briggs Institute Database of Systematic Reviews and Implementation Reports, Database of Abstracts of Reviews of Effects, PubMed, Embase, Ebsco (Academic Search Complete, AMED, Biomedical Reference Collection, CINAHL, Medline, PsycInfo, SPORTDiscus), Epistemonikos, PEDro and the PROSPERO register. The authors developed a comprehensive search strategy to identify papers relevant to the primary aims of the overview. To illustrate, the full electronic database search string for the CINAHL database is detailed in Box 1. In addition, reference lists of included reviews will be hand-searched to identify other potentially relevant reviews. In line with best practice guidelines for the conduction of umbrella reviews, our comprehensive search will also encompass a search for grey literature, as well as government and non-government organisations’ reports36.

Box 1. Search Strategy for CINAHL

S1: TI (falls OR fall* OR “accidental fall”) OR AB (falls OR fall* OR “accidental fall”)

S2: TI (stroke OR CVA OR cerebrovascular OR apoplexy OR vascular OR MS OR “multiple sclerosis” OR demyelin* OR PD OR “parkinson’s disease” OR “parkinson disease” OR parkinson* OR neurol*) OR AB (stroke OR CVA OR cerebrovascular OR apoplexy OR vascular OR MS OR “multiple sclerosis” OR demyelin* OR PD OR “parkinson’s disease” OR “parkinson disease” OR parkinson* OR neurol*)

S3: (TI stroke OR CVA OR cerebrovascular OR apoplexy OR vascular OR MS OR “multiple sclerosis” OR demyelin* OR PD OR “parkinson’s disease” OR “parkinson disease” OR parkinson* OR neurol* OR AB stroke OR CVA OR cerebrovascular OR apoplexy OR vascular OR MS OR “multiple sclerosis” OR demyelin* OR PD OR “parkinson’s disease” OR “parkinson disease” OR parkinson* OR neurol*) AND (S1 AND S2)

S4: TI (intervention OR prevention OR rehabilitation OR treatment OR therap*) OR AB (intervention OR prevention OR rehabilitation OR treatment OR therap*)

S5: (TI intervention OR prevention OR rehabilitation OR treatment OR therap* OR AB intervention OR prevention OR rehabilitation OR treatment OR therap*) AND (S3 AND S4)

S6: TI (systematic OR review OR “meta-analysis”) OR AB ( systematic OR review OR “meta-analysis”)

S7: (TI systematic OR review OR “meta-analysis” OR AB systematic OR review OR “meta-analysis”) AND (S5 AND S6)

Inclusion and exclusion criteria

This umbrella review will include quantitative systematic reviews (with or without meta-analysis), mixed-methods systematic reviews (quantitative elements only will be included) or pooled analyses and research syntheses investigating the effectiveness of falls prevention interventions for people with MS, PD and stroke. This umbrella review will include only research syntheses published in the English language due to resources. No restriction will be placed on date of publication. If a review is an update of a previous review, the most recent update will be included and the older versions will be excluded.

Potentially relevant papers will be assessed for inclusion as a systematic review by two independent reviewers (NO’M and AC/SC) using the JBI Critical Appraisal Checklist for Systematic Reviews and Research Syntheses32. Any disagreements between reviewers will be resolved through discussion or by a third reviewer (AC/SC) until consensus is achieved. Upon completion of this appraisal, literature reviews that do not include key features of accepted systematic review methodology, outlined by JBI37, will be excluded from this umbrella review. If necessary, the authors of the reviews will be contacted to clarify any unclear or missing details before the review is excluded.

The inclusion criteria based on population, intervention, comparison, outcome and study design (PICOS) are outlined in Table 1.

Table 1. Summary of inclusion criteria for systematic reviews of falls prevention interventions.

Study
characteristic
Inclusion criteria
PopulationPeople with Parkinson’s Disease
People with Multiple Sclerosis
People post-stroke
Studies with a combination of the above populations
Studies in which data regarding the above populations can be extracted
InterventionNon-pharmacological falls prevention interventions
ComparisonUsual or enhanced care
OutcomesPrimary outcomes: falls outcomes measured as a primary or secondary outcome
Secondary outcomes: outcomes relating to the effectiveness of the intervention (e.g. strength,
mobility, fatigue, participation, etc.)
Study designSystematic reviews of randomised controlled trials (RCTs) and quasi-RCTs
Systematic reviews of RCTs and all other study designs investigating falls prevention interventions

Study selection

The papers yielded from the search of each individual electronic database will be exported to the master reference management library Rayyan, where duplicate papers will then be removed. The titles and abstracts will be screened by two reviewers (NO’M and AC/SC) against the eligibility criteria for any obviously irrelevant papers. Following this, the full text of potentially relevant reviews will be screened by two independent reviewers (NO’M and AC/SC) to confirm inclusion in the final overview of reviews. Any discrepancies between reviewers will be resolved through a discussion or by a third reviewer (AC/SC) until consensus is achieved. A PRISMA flow diagram of the included studies will be completed.

Data extraction

Data will be extracted by one reviewer using a standardised data extraction form (NO’M). The extracted data will be verified by a second reviewer (AC/SC). Disagreements regarding data extraction will be resolved through discussion or by consulting a third reviewer (AC/SC) until consensus is achieved. The data extraction form will include the following:

  • 1. Citation details of included review

  • 2. Objectives of included review

  • 3. Type of review

  • 4. Participant characteristics

  • 5. Setting and context of the review

  • 6. Number of databases searched

  • 7. Date range over which database searching was conducted

  • 8. Date range over which studies included in the review that inform each outcome of interest were published

  • 9. Number of studies, types of studies and country of origin of studies included in each review

  • 10. Instrument used to critically appraise the primary studies and their quality rating

  • 11. Primary falls outcomes and secondary outcomes of interest reported in reviews

  • 12. Methods employed to synthesise the evidence

  • 13. Any comments or notes that the authors have regarding the included review

Methodological quality assessment

The methodological quality of included reviews will be assessed by two independent reviewers (NO’M) using the Assessment of Multiple Systematic Reviews 2 (AMSTAR 2) tool38. The AMSTAR 2 is a 16-item checklist utilised to assess the quality of systematic reviews that include randomised or non-randomised studies of healthcare interventions. Reviewers score each domain with ‘yes’ or ‘no’, or in some domains there is a third option of ‘partial yes’. The overall score of the AMSTAR 2 will be used to rate the quality of each included review investigating the effectiveness of falls prevention interventions as high, moderate, low or critically low38.

It has been suggested that the use of PRISMA in conjunction with a comprehensive, validated critical appraisal tool facilitates judgement not only of the methodological quality of the included reviews but also the general quality of reporting39. Consequently, the full text of all included reviews will be cross-checked against the PRISMA reporting guidelines checklist33,34.

Quality of evidence

The Grading of Recommendations Assessments, Development and Evaluation (GRADE) framework was designed to provide guidance for rating the quality of evidence and grading the strength of recommendations in healthcare40. This approach is primarily used to assess the quality of evidence in systematic reviews, but has been also applied to umbrella reviews in the absence of a more specific framework. The GRADE approach will be used to assess the quality of the evidence relating to the following outcomes included in RCTs in systematic reviews:

  • 1. Total number of falls

  • 2. Falls rate

  • 3. Number of fallers

Overlap of primary studies

Overlap of primary studies is a challenge unique to umbrella reviews. Presently, there is an absence of guidance on how best to deal with this phenomenon41. In the presence of complete overlap between reviews, the most recent review will be included in data synthesis and analysis. In the presence of partial overlap, all reviews will be included but the authors will note the degree of duplication and discuss its implications on the findings of this umbrella review.

Discordance between reviews

There are a number of reasons for discordant reviews and the conduction of umbrella reviews allows researchers to address the issue of discordance and identify its cause39. In the event of discordant reviews in our overview, the algorithm designed by Jadad et al. (1997) will be utilised to resolve issues of discordance42.

Data synthesis and analysis

This umbrella review will provide a summary of evidence table that will name the intervention, outline the included research synthesis and provide a clear indication of the results. Given the anticipated heterogeneity in populations, outcomes and analyses, the findings of included reviews will be summarised through a narrative synthesis with the quantitative tabulation of results as appropriate. Where possible, the sensitivity of the review findings will be considered in the context of its methodological quality, as determined by the AMSTAR 2, to examine the effects of synthesising reviews of varying quality. In the first instance, analyses will be completed using systematic reviews of any methodological quality that include all study designs. If sufficient reviews including randomised-controlled trials only are retrieved, a second analysis using this highest quality evidence will be completed. Comparisons between the two analyses will then be presented and discussed.

Dissemination

The findings of this umbrella review will be disseminated through the publication of peer-reviewed manuscripts. Additionally, findings will be presented at both national and international conferences.

Study status

The authors have commenced searches for this umbrella review.

Discussion

This umbrella review will use a robust methodology to present evidence regarding the effectiveness of non-pharmacological falls prevention interventions on falls outcomes among individuals with MS, PD and stroke. The development of falls prevention interventions for groups with mixed neurological diseases may improve the implementability of programmes in the community. Given the sparsity of studies investigating the effectiveness of interventions across several neurological diseases, an umbrella review presents a novel approach to synthesise existing falls literature to identify similarities or differences in effective interventions for people with stroke, MS and PD to facilitate the development of a mixed diagnoses intervention. This umbrella review will be the first of its kind to investigate the effectiveness of all non-pharmacological falls prevention interventions across several neurological diseases.

Data availability

Underlying data

No data are associated with this article.

Reporting guidelines

Figshare: PRISMA-P checklist for ‘Effectiveness of non-pharmacological falls prevention interventions for people with Multiple Sclerosis, Parkinson’s Disease and stroke: Protocol for an umbrella review’, https://doi.org/10.6084/m9.figshare.12063657.v143.

Data are available under the terms of the Creative Commons Attribution 4.0 International license (CC-BY 4.0).

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Version 2
VERSION 2 PUBLISHED 24 Apr 2020
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O'Malley N, Clifford AM, Comber L and Coote S. Effectiveness of non-pharmacological falls prevention interventions for people with Multiple Sclerosis, Parkinson’s Disease and stroke: protocol for an umbrella review [version 1; peer review: 3 approved with reservations] HRB Open Res 2020, 3:17 (https://doi.org/10.12688/hrbopenres.13023.1)
NOTE: it is important to ensure the information in square brackets after the title is included in all citations of this article.
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Key to Reviewer Statuses VIEW
ApprovedThe paper is scientifically sound in its current form and only minor, if any, improvements are suggested
Approved with reservations A number of small changes, sometimes more significant revisions are required to address specific details and improve the papers academic merit.
Not approvedFundamental flaws in the paper seriously undermine the findings and conclusions
Version 1
VERSION 1
PUBLISHED 24 Apr 2020
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Cite
Reviewer Report 29 Jul 2020
Vicki L Gray, Department of Physical Therapy and Rehabilitation Science, University of Maryland School of Medicine, Baltimore, MD, USA 
Approved with Reservations
VIEWS 22
This is a protocol for an umbrella review that will examine the effectiveness of non-pharmacological fall prevention interventions in people with Multiple Sclerosis, Parkinson’s Disease, and Stroke. The goal is to provide clinical recommendations that can span across these populations.
... Continue reading
CITE
CITE
HOW TO CITE THIS REPORT
Gray VL. Reviewer Report For: Effectiveness of non-pharmacological falls prevention interventions for people with Multiple Sclerosis, Parkinson’s Disease and stroke: protocol for an umbrella review [version 1; peer review: 3 approved with reservations]. HRB Open Res 2020, 3:17 (https://doi.org/10.21956/hrbopenres.14118.r27663)
NOTE: it is important to ensure the information in square brackets after the title is included in all citations of this article.
  • Author Response 01 Dec 2020
    Nicola O'Malley, School of Allied Health, Faculty of Education and Health Sciences, University of Limerick, Limerick, Ireland
    01 Dec 2020
    Author Response
    Many thanks for your time spent reviewing this protocol and for your constructive and insightful feedback and comments. We have reflected upon your feedback and made revisions to our manuscript ... Continue reading
COMMENTS ON THIS REPORT
  • Author Response 01 Dec 2020
    Nicola O'Malley, School of Allied Health, Faculty of Education and Health Sciences, University of Limerick, Limerick, Ireland
    01 Dec 2020
    Author Response
    Many thanks for your time spent reviewing this protocol and for your constructive and insightful feedback and comments. We have reflected upon your feedback and made revisions to our manuscript ... Continue reading
Views
22
Cite
Reviewer Report 24 Jul 2020
Feng Yang, Department of Kinesiology and Health, Georgia State University, Atlanta, Georgia, USA 
Caroline Simpkins, Department of Kinesiology and Health, Georgia State University, Atlanta, GA, USA 
Approved with Reservations
VIEWS 22
Falls are a common and serious health threat facing people with neurological diseases, such as multiple sclerosis, Parkinson’s disease, and stroke. The authors have made a strong argument for conducting an umbrella review to identify fall prevention interventions that are ... Continue reading
CITE
CITE
HOW TO CITE THIS REPORT
Yang F and Simpkins C. Reviewer Report For: Effectiveness of non-pharmacological falls prevention interventions for people with Multiple Sclerosis, Parkinson’s Disease and stroke: protocol for an umbrella review [version 1; peer review: 3 approved with reservations]. HRB Open Res 2020, 3:17 (https://doi.org/10.21956/hrbopenres.14118.r27665)
NOTE: it is important to ensure the information in square brackets after the title is included in all citations of this article.
  • Author Response 01 Dec 2020
    Nicola O'Malley, School of Allied Health, Faculty of Education and Health Sciences, University of Limerick, Limerick, Ireland
    01 Dec 2020
    Author Response
    Many thanks for your time spent reviewing this protocol and for your constructive and insightful feedback and comments. We have reflected upon your feedback and made revisions to our manuscript ... Continue reading
COMMENTS ON THIS REPORT
  • Author Response 01 Dec 2020
    Nicola O'Malley, School of Allied Health, Faculty of Education and Health Sciences, University of Limerick, Limerick, Ireland
    01 Dec 2020
    Author Response
    Many thanks for your time spent reviewing this protocol and for your constructive and insightful feedback and comments. We have reflected upon your feedback and made revisions to our manuscript ... Continue reading
Views
33
Cite
Reviewer Report 29 Apr 2020
Ylva Nilsagård, Health Care Management, Faculty of Medicine and Health, Örebro University, Örebro, Sweden 
Approved with Reservations
VIEWS 33
This is a study protocol for an umbrella review - registered in PROPSPERO - that will include systematic reviews of randomised controlled trials and studies investigating the effects of non-pharmacological falls prevention interventions on falls outcomes. The PRISMA checklist was ... Continue reading
CITE
CITE
HOW TO CITE THIS REPORT
Nilsagård Y. Reviewer Report For: Effectiveness of non-pharmacological falls prevention interventions for people with Multiple Sclerosis, Parkinson’s Disease and stroke: protocol for an umbrella review [version 1; peer review: 3 approved with reservations]. HRB Open Res 2020, 3:17 (https://doi.org/10.21956/hrbopenres.14118.r27347)
NOTE: it is important to ensure the information in square brackets after the title is included in all citations of this article.
  • Author Response 01 Dec 2020
    Nicola O'Malley, School of Allied Health, Faculty of Education and Health Sciences, University of Limerick, Limerick, Ireland
    01 Dec 2020
    Author Response
    Many thanks for your time spent reviewing this protocol and for your constructive and insightful feedback and comments. We have reflected upon your feedback and made revisions to our manuscript ... Continue reading
COMMENTS ON THIS REPORT
  • Author Response 01 Dec 2020
    Nicola O'Malley, School of Allied Health, Faculty of Education and Health Sciences, University of Limerick, Limerick, Ireland
    01 Dec 2020
    Author Response
    Many thanks for your time spent reviewing this protocol and for your constructive and insightful feedback and comments. We have reflected upon your feedback and made revisions to our manuscript ... Continue reading

Comments on this article Comments (0)

Version 2
VERSION 2 PUBLISHED 24 Apr 2020
Comment
Alongside their report, reviewers assign a status to the article:
Approved - the paper is scientifically sound in its current form and only minor, if any, improvements are suggested
Approved with reservations - A number of small changes, sometimes more significant revisions are required to address specific details and improve the papers academic merit.
Not approved - fundamental flaws in the paper seriously undermine the findings and conclusions

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