Risk assessment tools used for preventing pressure ulcers

What is the aim of this review?

The aim of this review was to find out what effect the use of risk assessment tools has on the development of new pressure ulcers, among people at risk of pressure ulcer development. Many different pressure ulcer risk assessment tools are used in clinical practice and it is not known which one is the best. Researchers from Cochrane collected and analysed all relevant studies (randomised controlled trials) to answer this question and found two relevant studies.

Key messages

We cannot be certain whether the use of a risk assessment tool makes any difference to the number of new pressure ulcers that develop among people who are at risk. The certainty of evidence ranged from low to very low.

What was studied in the review?

Pressure ulcers (also known as bed sores, pressure sores, pressure injuries and decubitus ulcers) are areas of localised injury to the skin and underlying tissue, usually over a bony part of the body such as the hip or heel. These ulcers develop as a result of pressure, or pressure in combination with shear forces (squeezing and stretching soft tissues between bony structures and the skin). Pressure ulcers mainly occur in people who have limited mobility or nerve damage, such as older people, people with spinal injuries, or long-term hospital patients. Pressure ulcer risk assessment is part of the process used to identify individuals at risk of developing a pressure ulcer. Use of a risk assessment tool is recommended by many international guidelines on pressure ulcer prevention. Different tools are used for pressure ulcer risk assessment. We wanted to find out which is the most effective in preventing pressure ulcers from developing. We also wanted to find out which risk assessment tools reduced the time for a pressure ulcer to develop and the severity of the pressure ulcer.

What are the main results of the review?

We found two relevant studies, dating from 2009 and 2011. Both of the included studies had three arms. One study compared Braden risk assessment and training, to training and risk assessment using clinical judgement, or risk assessment using clinical judgement alone. The second study compared Waterlow risk assessment to Ramstadius risk assessment, or risk assessment using clinical judgement. The studies involved 1,487 people at risk of developing pressure ulcers. In the first study, no information was provided on age or gender distribution. In the second study, 50.3% (619) of the participants were male, with an average age of 62.6 years. The first study did not state any source of funding. The second study was funded by research grants from the Queensland Nursing Council, the Royal Brisbane and Women’s Hospital Private Practice Fund, the Royal Brisbane and Women’s Hospital Research Foundation and a Queensland Health Nursing Research Grant.

We cannot be certain whether use of a risk assessment tool makes any difference to the prevention of pressure ulcers, compared with the use of clinical judgement. The results of the studies did not show differences in the number of pressure ulcers that developed among the participants and one study did not show a difference in the severity of pressure ulcers that developed. We assessed the certainty of the evidence as low, or very low, because not all the people completed one of the studies, and in both studies the results varied widely, and the staff knew which study group the patient was in. The outcomes for time to pressure ulcer development, and pressure ulcer prevalence, were not reported on by either study.

How up to date is this review?

We searched for studies that had been published up to February 2018.

Authors' conclusions: 

We identified two studies which evaluated the effect of risk assessment on pressure ulcer incidence. Based on evidence from one study, we are uncertain whether risk assessment using the Braden tool makes any difference to pressure ulcer incidence, compared with training and risk assessment using clinical judgement, or risk assessment using clinical judgement alone. Risk assessment using the Waterlow tool, or the Ramstadius tool may make little or no difference to pressure ulcer incidence, or severity, compared with clinical judgement. The low, or very low certainty of evidence available from the included studies is not reliable enough to suggest that the use of structured and systematic pressure ulcer risk assessment tools reduces the incidence, or severity of pressure ulcers.

Read the full abstract...
Background: 

Use of pressure ulcer risk assessment tools or scales is a component of the assessment process used to identify individuals at risk of developing a pressure ulcer. Use of a risk assessment tool is recommended by many international pressure ulcer prevention guidelines, however it is not known whether using a risk assessment tool makes a difference to patient outcomes. We conducted a review to provide a summary of the evidence pertaining to pressure ulcer risk assessment in clinical practice, and this is the third update of this review.

Objectives: 

To assess whether using structured and systematic pressure ulcer risk assessment tools, in any healthcare setting, reduces the incidence of pressure ulcers.

Search strategy: 

In February 2018 we searched the Cochrane Wounds Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE (including In-Process & Other Non-Indexed Citations); Ovid Embase; and EBSCO CINAHL Plus. We also searched clinical trials registries for ongoing and unpublished studies, and scanned reference lists of relevant included studies as well as reviews, meta-analyses and health technology reports to identify additional studies. There were no restrictions with respect to language, date of publication or study setting.

Selection criteria: 

Randomised controlled trials (RCTs) comparing the use of structured and systematic pressure ulcer risk assessment tools with no structured pressure ulcer risk assessment, or with unaided clinical judgement, or RCTs comparing the use of different structured pressure ulcer risk assessment tools.

Data collection and analysis: 

Two review authors independently performed study selection, data extraction, 'Risk of bias' assessment and GRADE assessment of the certainty of evidence.

Main results: 

We included two studies in this review (1,487 participants). We identified no new trials for this latest update.

Both studies were undertaken in acute-care hospitals. In one study, patients were eligible if they had a Braden score of 18 or less. In the second study all admitted patients were eligible for inclusion, once they were expected to have a hospital stay of more than three days and they had been in hospital for no more than 24 hours before baseline assessment took place. In the first study, most of the participants were medical patients; no information on age or gender distribution was provided. In the second study, 50.3% (619) of the participants were male, with a mean age of 62.6 years (standard deviation (SD): 19.3), and 15.4% (190) were admitted to oncology wards.

The two included studies were three-armed studies. In the first study the three groups were: Braden risk assessment tool and training (n = 74), clinical judgement and training (n = 76) and clinical judgement alone (n = 106); follow-up was eight weeks. In the second study the three groups were: Waterlow risk assessment tool (n = 411), clinical judgement (n = 410) and Ramstadius risk assessment tool (n = 410); follow-up was four days. Both studies reported the primary outcome of pressure ulcer incidence and one study also reported the secondary outcome, severity of new pressure ulcers.

We are uncertain whether use of the Braden risk assessment tool and training makes any difference to pressure ulcer incidence, compared to risk assessment using clinical judgement and training (risk ratio (RR) 0.97, 95% confidence interval (CI) 0.53 to 1.77; 150 participants), or compared to risk assessment using clinical judgement alone (RR 1.43, 95% CI 0.77 to 2.68; 180 participants). We assessed the certainty of the evidence as very low (downgraded twice for study limitations and twice for imprecision).

Risk assessment using the Waterlow tool may make little or no difference to pressure ulcer incidence, or to pressure ulcer severity, when compared to risk assessment using clinical judgement (pressure ulcers of all stages: RR 1.10, 95% CI 0.68 to 1.81; 821 participants; stage 1 pressure ulcers: RR 1.05, 95% CI 0.58 to 1.90; 821 participants; stage 2 pressure ulcers: RR 1.25, 95% CI 0.50 to 3.13; 821 participants), or risk assessment using the Ramstadius tool (pressure ulcers of all stages: RR 1.41, 95% CI 0.83 to 2.39; 821 participants; stage 1 pressure ulcers: RR 1.16, 95% CI 0.63 to 2.15; 821 participants; stage 2 pressure ulcers: RR 2.49, 95% CI 0.79 to 7.89; 821 participants). Similarily, risk assessment using the Ramstadius tool may make little or no difference to pressure ulcer incidence, or to pressure ulcer severity, when compared to risk assessment using clinical judgement (pressure ulcers of all stages: RR 0.79, 95% CI 0.46 to 1.35; 820 participants; stage 1 pressure ulcers: RR 0.90, 95% CI 0.48 to 1.68; 820 participants; stage 2 pressure ulcers: RR 0.50, 95% CI 0.15 to 1.65; 820 participants). We assessed the certainty of the evidence as low (downgraded once for study limitations and once for imprecision).

The studies did not report the secondary outcomes of time to ulcer development, or pressure ulcer prevalence.