Quantitive research on pressure injury prevention

1Wung Buh A, et al. BMJ Open 2021;11:e043042. doi:10.1136/bmjopen-2020-043042

Open access

Effects of implementing Pressure Ulcer
Prevention Practice Guidelines (PUPPG)
in the prevention of pressure ulcers
among hospitalised elderly patients: a
systematic review protocol

Amos Wung Buh,1 Hassan Mahmoud,2 Wenjun Chen ,3,4
Matthew D F McInnes,2,5,6 Dean A Fergusson 6

To cite: Wung Buh A,
Mahmoud H, Chen W, et al.
Effects of implementing
Pressure Ulcer Prevention
Practice Guidelines (PUPPG)
in the prevention of pressure
ulcers among hospitalised
elderly patients: a systematic
review protocol. BMJ Open
2021;11:e043042. doi:10.1136/
bmjopen-2020-043042

► Prepublication history and
additional material for this paper
is available online. To view these
files, please visit the journal
online (http:// dx. doi. org/ 10.
1136/ bmjopen- 2020- 043042).

AWB and HM contributed
equally.

AWB and HM are joint first
authors.

Received 23 November 2020
Revised 08 February 2021
Accepted 17 February 2021

For numbered affiliations see
end of article.

Correspondence to
Wenjun Chen;
[email protected] uottawa. ca

Protocol

© Author(s) (or their
employer(s)) 2021. Re- use
permitted under CC BY- NC. No
commercial re- use. See rights
and permissions. Published by
BMJ.

ABSTRACT
Introduction Pressure ulcers are serious and potentially
life- threatening problems across all age groups and across
all medical specialties and care settings. The hospitalised
elderly population is the most common group to develop
pressure ulcers. This study aims to systematically review
studies implementing pressure ulcer prevention strategies
recommended in the Pressure Ulcer Prevention Practice
Guidelines for the prevention of pressure ulcers among
hospitalised elderly patients globally.
Methods and analysis A systematic review of all studies
that have assessed the use of pressure ulcer prevention
strategies in hospital settings among hospitalised elderly
patients shall be conducted. A comprehensive search of
all published articles in Medline Ovid, Cumulative Index
to Nursing and Allied Health Literature, PubMed, Embase,
Cochrane library, Scopus and Web of Science will be done
using terms such as pressure ulcers, prevention strategies,
elderly patients and hospital. Studies will be screened
for eligibility through title, abstract and full text by two
independent reviewers. Study quality and risk of bias will
be assessed using the Joanna Briggs Institute for Meta-
Analysis of Statistics Assessment and Review Instrument.
If sufficient data are available, a meta- analysis will be
conducted to synthesise the effect size reported as OR
with 95% CIs using both fixed and random effect models.
I2 statistics and visual inspection of the forest plots will
be used to assess heterogeneity and identify the potential
sources of heterogeneity. Publication bias will be assessed
by visual inspections of funnel plots and Egger’s test.
Ethics and dissemination No formal ethical approval or
consent is required as no primary data will be collected.
We aim to publish the research findings in a peer- reviewed
scientific journal to promote knowledge transfer, as well
as in conferences, seminars, congresses or symposia in a
traditional manner.
PROSPERO registration number CRD42019129088.

BACKGROUND
Pressure ulcers (PU) also known as pressure
injuries are areas of localised damage to the
skin and/or underlying structures due to

pressure and/or friction and shear.1 They
are serious and potentially life- threatening
problems across all age groups from the very
young to the very old and across all medical
specialties and care settings.2 It has been
documented that hospital admissions due to
PU are 75% higher than admissions for any
other medical conditions and that, the conse-
quences of PU development in hospitalised
patients are particularly serious.2 Patients
with hospital admission PU are three times
more likely to be discharged to long- term
care facilities and mortality of these patients is
twice that of patients without hospital admis-
sion PU.3 The cost of treatment of PU is 2.5
times than its prevention, and PU increases
the length of stay in the hospital from 4 to

Strengths and limitations of this study

► This is a systematic review and meta- analysis of
randomised controlled trials.

► This review will be the first to synthesise the ev-
idence regarding the effectiveness of guidelines
used in pressure ulcer prevention for elderly pa-
tients in hospitals and offer the highest level of
evidence for informed decisions on use of Pressure
Ulcer Prevention Practice Guidelines (PUPPG) in
prevention pressure ulcers in the elderly patients in
hospital.

► There may be heterogeneity of interventions used on
eligible studies and incomplete information reported
about the interventions in the literature which could
limit our ability to statistically compare the effective-
ness of interventions.

► The main limitation of this review might be scarcity
of randomised controlled trials on the use of PUPPG
for preventing pressure ulcers in elderly patients,
publication bias and methodological quality of grey
literature that shall be found.

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30 days, decreases quality of life, and increases pain,
morbidity and mortality.4

On international level, hospital- acquired PUs (some-
times called decubitus ulcers) are very common.5
Although many of these cases are preventable, their point
prevalence in Canadian hospitals for example is measured
to be 25.1%.6 Unfortunately, the high rates of such condi-
tion are associated with subsequent high burden on the
healthcare system and the national economy considering
the high cost of their management, and the frequent
occurrence of associated significant morbidity and
mortality.5 According to the Ontario Case Costing Initia-
tive database in 2013 using the European Pressure Ulcer
Advisory Panel (EPUAP) staging system, it was estimated
that the cost of management of stage II ulcer is up to
US$40 000 and can reach more than double this price for
managing a single case of stage IV ulcer.7 A good example
of the burden that PU add to the national economy was
measured in USA; it was estimated that hospital acquired
PUs increase the financial expenses on healthcare systems
between US$6 and US$15 billion annually.8

The National Pressure Ulcer Advisory Panel (NPUAP),
the EPUAP and the Pan Pacific Pressure Injury Alliance
(PPPIA)9 have defined PU as a ‘lesion or a trauma to the
skin and/or underlying tissue usually over a bony promi-
nence and is the result of undiminished pressure, or pres-
sure combination with shear, friction and moisture’. It is
a degenerative progress attributable to biological tissues
(skin and underlying tissues) being exposed to pressure
and shearing forces. The pressure constrains the proper
blood circulation and causes cell death, tissue necrosis
and the development of ulcers.9 While the quality of PU
prevention and treatment has increased considerably
over the past years, PUs remains a global concern because
of its frequency of occurrence and negative consequences
for patients and families as well as for the healthcare
system.10 Incidence of PUs for hospitalised patients
ranges from 9% to 18%, among which the elderly popu-
lation appears to be the most common group to develop
the ulcers.11 At the same time, many elderly patients are
more vulnerable to be ‘stuck’ at a certain stage of PU for
a long period of time and sometimes for the remainder of
their lives.12 This may result in longer length of hospital
stay, heavier burdens for the healthcare system and family
members, worst quality of life for elderly patients, which
may also influence their mental health such as emotional
stability.13 14

NPUAP, EPUAP and PPPIA9 developed the Pressure
Ulcer Prevention Practice Guideline (PUPPG), which
involves a range of evidence- based recommendations for
PUs prevention that could be applied by healthcare profes-
sionals globally. Frequently used PU prevention strategies
recommended in this guideline includes PU risk assess-
ment, regular repositioning, prevention management
plan, appropriate use of support surfaces and protection,
continence management, patient education, skin protec-
tion, nutritional assessment and adequate nutrition.15
It also includes some recommendations specifically for

elderly people—‘protect aged skin from skin injury asso-
ciated with pressure and shear forces’, taking into consid-
eration that an aged person’s skin is vulnerable.15

A number of studies have been conducted on the
implementation of PU prevention strategies among
hospitalised patients. One cluster randomised trial
conducted in Canada revealed that multidisciplinary PU
prevention groups are more cost effective than usual care
and yields no significant improvement in the treatment
of PUs.16 Despite the existence of the guidelines on the
prevention of PU, their effective utilisation in preventing
PUs among hospitalised elderly patients varies in settings
and countries. Also, although a number of studies have
assessed strategies used in preventing PUs, there appears
to be little or no information on systematic reviews that
have assessed the effectiveness of guidelines used in PU
prevention for elderly patients in hospitals. This study,
therefore, aims to systematically review studies imple-
menting PU prevention strategies recommended in the
PUPPG for the prevention of PUs among hospitalised
elderly patients globally.

OBJECTIVE
The objective of this review is to assess the effectiveness
of each of the strategies included in the PUPPG guide-
line in reducing the incidence and prevalence of hospital
acquired PUs in hospitalised elderly patients in compar-
ison to no strategy (usual practice), or other strategies.
The review question is: what is the effectiveness of imple-
menting each of the PU prevention strategies included in
the PUPPG in decreasing the incidence and prevalence
of PUs among hospitalised elderly patients compared
with no strategies (basic usual care) or different preven-
tion strategies?

METHODS
Study design
This will be a systematic review and meta- analysis of
published and unpublished studies that have assessed the
use of PU prevention strategies in hospital settings among
hospitalised elderly patients. The systematic review
protocol has been developed and reported following
the Preferred Reporting Items for Systematic Reviews
and Meta- Analyses (PRISMA) criteria (see online supple-
mental appendix 1).17

Inclusion criteria
Population included
This systematic review will focus on studies that involved
all vitally stable (not admitted in the intensive care unit)
bed ridden hospitalised patients aged 60 or above.

Interventions
All studies that assessed the effect of PU preventive strat-
egies found in the PUPPG, that were implemented on
vitally stable bed ridden hospitalised patients aged 60 and

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above with an aim to decrease the occurrence of PUs, will
be included in this review. Interventions will be limited to
use of risk assessment, skin assessment, skin care, nutri-
tion, position and repositioning, education and training,
and medical devices care.

Comparator
Interventions will be compared with other strategies
to identify the most effective among them and/or will
also be compared with no interventions (regular basic
management).

Outcomes
In this study, the primary outcome will be directly related
to the incidence of the disease among elderly hospitalised
patients (incidence shall be considered as the propor-
tion of hospitalised patients who developed PUs while in
hospital). Included studies must measure study duration
related incidence of the disease and/or its point preva-
lence and /or stage of PU (severity) as a measure of the
effectiveness of the preventive strategies.

Types of studies
We will focus only on Quantitative studies—experimental
and quasi- experimental studies. These might include
randomised and non- randomised controlled trials in
addition to comparative and before- and- after studies.

Language
Only studies written in English will be included in this
systematic review.

SEARCH STRATEGY
We will use a three- step strategy to find published and
unpublished studies on PUs and their management. First,
we will conduct an initial search through the Medline
Ovid database using an analysis of text words found in the
title and abstract, and the index terms used to describe
the article. Second, we will use identified keywords and
index terms to search for studies in identified databases.
Finally, we will use the reference list of selected studies
from the first and second searches to look for additional
studies not found in the databases. For this study, we will
consider only studies either published or unpublished in
English.

The databases that shall be searched for this review will
include Medline Ovid, Cumulative Index to Nursing and
Allied Health Literature, PubMed, Embase, Cochrane
library, Scopus and Web of Science. See online supple-
mental appendix 2 for the example searching strategy
and results in Medline (Ovid). All these databases will
provide published studies. To find unpublished studies
on our topic, we will use Google, Grey Literature reports
and the Centers for Disease Control and Prevention.

The keywords we will use for our initial searches in
Medline Ovid will include ‘pressure ulcers’, ‘pressure
sore’, ‘bed sore’, ‘pressure injuries’, ‘prevention strate-
gies’, ‘elderly patients’ and ‘hospital’.

Study screening and selection
The titles, abstracts and full text of studies selected for this
study will be reviewed by two independent researchers to
identify studies that potentially meet the inclusion criteria
outlined above. The Covidence software will be used for
title, abstract and full- text screening. After importing
references and inclusion/exclusion criteria into the Covi-
dence software, two independent reviewers will screen
titles of included studies according to the eligible criteria.
Conflicts between those two reviewers will be resolved
through discussion with a third reviewer. The same proce-
dures shall be used for abstract screening. Following the
abstract screening, full texts of these potentially eligible
studies will be retrieved and independently assessed for
eligibility by two reviewers. Any disagreement between
the two reviewers over the eligibility of a particular study
will also be resolved through discussion with the third
reviewer. The process of study selection will be reported
using the PRISMA flow diagram.17

Assessment of methodological quality
Two independent reviewers will be used to assess the
methodological validity of the quantitative papers that
will be selected for retrieval prior to their inclusion in
the review using standard critical appraisal tools from
the Joanna Briggs Institute for Meta- Analysis of Statistics
Assessment and Review Instrument (see online supple-
mental appendix 3). All disagreement between the two
reviewers shall be settled through discussions.

Data extraction
After screening and selecting studies, key information
from those studies will be extracted into an excel sheet for
further analysis. We shall use a data extraction tool adapted
from the standardised data extraction tool from the Joanna
Briggs Institute Meta- Analysis of Statistics Assessment and
Review Instrument (JBI- MAStARI). Considering the infor-
mation, we will need for the data synthesis of our study, we
shall use the JBI- MAStARI to develop a data extraction tool
specifically for quantitative research data extraction (see
online supplemental appendix 4). The tool will be used to
extract: (1) Study characteristics of reviewed papers, such
as authors, year of publication, journal; (2) Methods of the
study, including study design (randomised control trial
(RCT), quasi- RCT, longitudinal, retrospective), research
purpose and/or questions; (3) participant characteristics,
country where the study took place, setting, population,
sample size, age, sex, ethnicity, socioeconomic status and/
or education level; (4) PU prevention strategies used in
experimental group and control group (if applicable),
(5) outcome measures and results and (6) conclusions of
reviewed papers and any comments from reviewers. Two
reviewers will independently perform data extraction.
Authors of reviewed papers will be contacted in case of
any missing details about their studies.

Data synthesis
A meta‐analysis of outcomes combining various studies
included in the review shall be done. We will assess

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statistical heterogeneity with I2, which will indicate the
percentage of the total variation across studies: 0%–40%
low heterogeneity, 30%–60% moderate heterogeneity,
50%–90% may represent substantial heterogeneity and
75%–100% is considerable heterogeneity. If there is a
substantial amount of heterogeneity (75%), then sources
of heterogeneity will be examined through subgroup
and sensitivity analyses. We will also use χ2 test to test the
heterogeneity and consider p<0.05 as statistically signifi-
cant. A fixed‐effects model will be selected for significant
homogeneous studies; otherwise we will apply a random‐
effects model. All outcomes will be summarised using
ORs and 95% CI. An OR <1 will represent a lower rate of
outcome among the group of patients who were treated
following the guidelines. Publication bias will be assessed
by visual inspections of funnel plots and Egger’s test.

We will also provide a narrative synthesis of the find-
ings from the included studies. The narrative synthesis
shall be structured by describing the studies according to
the type of intervention used. This will include the three
categories of interventions recommend in the PUPPG
guideline9:
1. Prevention of PUs, including risk factors and risk as-

sessment, skin and tissue assessment, preventive skin
care and emerging therapies for prevention of PUs.

2. Interventions for prevention and treatment of PUs,
such as nutrition in PU prevention and treatment, re-
positioning and early mobilisation, repositioning to
prevent and treat PUs, support surface and medical
device- related PUs.

3. Treatment of PUs, for example, assessment of PUs and
monitoring of healing, pain assessment and treatment,
wound care, assessment and treatment of infection
and biofilms, wound dressings for treatment of PUs
and surgery for PUs. Results will be presented in tables,
figures and graphs, followed by discussion.
Publication bias will be assessed in all analyses synthe-
sising 10 or more studies to ensure adequate power in
the analysis.18 For investigation of the effect of small
studies and publication bias, data from included stud-
ies will be entered into a funnel plot asymmetry test if
we have at least 10 studies in the meta- analysis. Egger’s
statistical test will be implemented using STATA/SE
V.13 (StataCorp). The quality of supporting evidence
will be assessed by the Grades of Recommendation,
Assessment, Development and Evaluation.19

Patient and public involvement
No patient involved.

Ethics and dissemination
This review will only use published literature and will
not recruit participants. Therefore, no formal ethical
approval or consent is necessary. It is anticipated that
this systematic review will provide a detailed summary
of the evidence of the effectiveness of the PUPPG in
preventing the occurrence of PUs among elderly patients
in hospital. It is also expected that the study will provide

recommendations on the best PU preventive strategies
applicable in healthcare settings. We aim to publish the
research findings in a peer- reviewed scientific journal to
promote knowledge transfer, as well as in various media,
such as: conferences, seminars, congresses or symposia in
a traditional manner.

Author affiliations
1Interdisciplinary School of Health Sciences, University of Ottawa, Ottawa, Ontario,
Canada
2School of Epidemiology and Public Health, Faculty of Medicine, University of
Ottawa, Ottawa, Ontario, Canada
3School of Nursing, University of Ottawa, Ottawa, Ontario, Canada
4Xiangya School of Nursing, Central South University, Changsha, Hunan, China
5Department of Radiology, University of Ottawa, Ottawa, Ontario, Canada
6Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa,
Ontario, Canada

Acknowledgements The authors would like to thank Lindsey Sikora (librarian) for
counselling in developing the searching strategies.

Contributors AWB, HM and WC contributed to the conception of the research
question and writing of the protocol. HM, AWB, WC, MDFM and DAF contributed to
the development of search strategies, eligibility criteria and methodology for data
synthesis. HM, AWB, WC, MDFM and DAF contributed to drafting of the protocol and
provided approval for the final version of this protocol. HM, AWB and WC will work
in duplicate to screen the titles and abstracts of all the materials obtained using
the search strategy to exclude the articles that do not meet the eligibility criteria.
HM, AWB and WC will evaluate the potentially eligible studies with the full text and
further exclude studies with documentation of the reason for exclusion. All authors
will contribute to the bias assessment strategy and data extraction criteria. HM,
AWB and WC will independently extract data from the included studies. HM, AWB
and WC will analyse the data and draft the manuscript. All authors will read, provide
feedback and approve the final manuscript.

Funding This work was supported by Hunan Provincial Key Laboratory of
Nursing, grant number (2017TP1004), Hunan Provincial Science and Technology
Department, China.

Competing interests None declared.

Patient consent for publication Not required.

Provenance and peer review Not commissioned; externally peer reviewed.

Supplemental material This content has been supplied by the author(s). It has
not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been
peer- reviewed. Any opinions or recommendations discussed are solely those
of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and
responsibility arising from any reliance placed on the content. Where the content
includes any translated material, BMJ does not warrant the accuracy and reliability
of the translations (including but not limited to local regulations, clinical guidelines,
terminology, drug names and drug dosages), and is not responsible for any error
and/or omissions arising from translation and adaptation or otherwise.

Open access This is an open access article distributed in accordance with the
Creative Commons Attribution Non Commercial (CC BY- NC 4.0) license, which
permits others to distribute, remix, adapt, build upon this work non- commercially,
and license their derivative works on different terms, provided the original work is
properly cited, appropriate credit is given, any changes made indicated, and the use
is non- commercial. See: http:// creativecommons. org/ licenses/ by- nc/ 4. 0/.

ORCID iDs
Wenjun Chen http:// orcid. org/ 0000- 0001- 5398- 8508
Dean A Fergusson http:// orcid. org/ 0000- 0002- 3389- 2485

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