The objectives of this review are to identify patient clinical factors that may be associated with PI development in adult intensive care. In addition, this review seeks to determine the effect size of the association between identified factors and PI development. The systematic review will synthesise existing knowledge and make recommendations for future research.
The search strategy aims to find both published and unpublished studies exploring the risk factors that are associated with PI development in intensive care. The literature will be searched using medical subject headings (MeSH) and combinations of key terms. The search is limited to English language publications with no restriction on the year of publication.
The electronic databases searches will include: the Cochrane (1991 (established) to present); PubMed/MEDLINE (1969–present); CINAHL (EBSCOhost) (1989 to present); EMBASE (1966–present); Scopus (1975–present); PsycINFO (2009 to present); Proquest (1929 to present); Networked Digital Library of Theses and Dissertations; Australian Digital Theses Program, Grey literature, and Google scholar. In addition, the reference lists of articles meeting the criteria for this review will be searched for further relevant studies.
The search syntax will be designed by applying the guidance of the Cochrane Handbook to retrieve the relevant results. Search strings will be focused on the terms pressure ulcer, pressure injury, risk factors, predictors, adult intensive care, and their synonyms.
Types of study to be included
Eligible quantitative studies published in peer-reviewed journals will be included in this review. The systematic review will consist of studies using either epidemiological designs such as retrospective or prospective cohort studies, or experimental designs such as randomized controlled trials or quasi-experimental trials, where analyses for potential factors of PI development in intensive care have been reported. . Cross-sectional, qualitative, case studies and abstract-only reports, for which full text is not available, will be excluded from this review.
Condition or domain being studied
Risk factors for pressure injury/ulcer development in critically ill patients in the intensive care unit.
This review will consider studies that included adult critically ill patients aged 18 or above, who have not been diagnosed with community acquired PI.
No restriction will be imposed for risk factors that are significantly associated with PI development in intensive care. In addition, studies that examine the factors of PIs development for adults across hospitals but that have separate statistical analyses reported for PI development in adult intensive care will also be included.
The inclusion criteria are:
(i) length of follow-up at least 48 hours
(ii) multivariate analyses undertaken to identify factors affecting pressure ulcer outcome and
(iii) not specific to geographical areas.
The exclusion criteria are:
(i) observational studies will be excluded if >20% of the study sample were excluded from analysis for reasons including withdrawal, death, loss to follow-up and missing records
(ii) Control trial studies will be excluded unless all of the following minimum criteria applied: randomised allocation to treatment, and intention to treat analyses.
Studies conducted in intensive/critical care settings will be included.
This review will consider studies that include all stages of PI or equivalent as the outcome measure. According to the National Pressure Ulcer Advisory Panel, European Pressure Ulcer Advisory Panel and Pan Pacific Pressure Injury Alliance Clinical practice guidelines the PI stages reflect the level of skin tissue damage
Data extraction, (selection and coding)
Data will be extracted independently using the data extraction form. This form will include: the study characteristics (for example, study population, recruitment type used, PI definition and analysis method) and risk factors investigated in the multivariate models, including those found to be significant. Non-significant factors through using a stepwise regression will be included if it reported as independent correlated variables to PI development. Disagreement will be reconciled by mutual agreement. In addition, authors will be contacted if papers were unobtainable or methods reported needed clarification.
Risk of bias (quality) assessment
The authors will undertake the risk of bias assessment of the included studies independently, as guided by the assessment framework for assessing quality in prognostic studies and methodological considerations in the analysis and publication of observational studies.
The methodological quality of eligible studies will be assessed and critically appraised by two independent reviewers (the authors) using the assessment framework that is designed to appraise quality in prognostic studies and methodological considerations in the analysis and publication of observational studies. Any disagreements that arise between the reviewers will be resolved through discussion, or with a third reviewer.
This quality assessment tool will rate the relevant methodological parameters of studies across seven areas: selection bias (selection of target population), confounders (whether confounders were controlled using appropriate adjustment), data collection methods (validity and reliability by using a clear definition or description of the risk factor), continuous variable are reported (cut point), range of potential risk factors are measured, withdrawals and dropouts (dropout rates and completion of study rates), and no selective reporting of results.
In addition, this tool has four considerations to apprise domains quality:
1. Is there a sufficient number of events (rule of thumb, 10 events per risk factor)?
2. Is there sufficient presentation of data to assess the adequacy of method and analysis?
3. Is the strategy for model building (i.e. inclusion of variables) appropriate and based upon a conceptual framework?
4. Is the selected model adequate for the design?
Each criterion was assessed as being met (yes/no/partial/unsure). Consequently, assessment of domain criteria will assist the classification of overall study quality.
Strategy for data synthesis
The meta-analysis may not be conducted due to the clinical or statistical heterogeneity of the eligible studies. However, if included studies are sufficiently homogenous and rigorous, a meta-analysis will be conducted. A relative risk will be the appropriate indicator of effect for potential correlates in this review with a 95% confidence interval (CI) calculated for binary outcomes (PI development). However, given the considerable clinical and design heterogeneity in the included studies, the findings are presented in narrative form including tables to aid in data presentation where appropriate.
Analysis of subgroups or subsets
This review will be published in an open access journal; BMC Systematic Reviews.
Contact details for further information
Intensive Care Services
Level 3 Ned Hanlon Building
Royal Brisbane & Women's Hospital (RBWH)
Butterfield St., Herston, Queensland, 4006. Australia
Organisational affiliation of the review
Queensland University of Technology (QUT)
Professor Fiona Coyer, RBWH and QUT Mrs Nahla Tayyib, QUT
Anticipated or actual start date
02 May 2016
Anticipated completion date
30 July 2016
Conflicts of interest
Professor Coyer undertakes paid consultancy for 3M and Teleflex.
Subject index terms status
Subject indexing assigned by CRD
Subject index terms
Critical Care; Critical Illness; Humans; Intensive Care Units; Pressure Ulcer
Stage of review
Date of registration in PROSPERO
27 April 2016
Date of publication of this revision
27 April 2016
Stage of review at time of this submission
Piloting of the study selection process
Formal screening of search results against eligibility criteria
Risk of bias (quality) assessment
PROSPERO This information has been provided by the named contact for this review. CRD has accepted this information in good faith and registered the review in PROSPERO. CRD bears no responsibility or liability for the content of this registration record, any associated files or external websites.