Risk assessment scales for pressure ulcer prevention: a systematic review

AIM: This paper reports a systematic review conducted to determine the effectiveness of the use of risk assessment scales for pressure ulcer prevention in clinical practice, degree of validation of risk assessment scales, and effectiveness of risk assessment scales as indicators of risk of developing a pressure ulcer. BACKGROUND: Pressure ulcers are an important health problem. The best strategy to avoid them is prevention. There are several risk assessment scales for pressure ulcer prevention which complement nurses' clinical judgement. However, some of these have not undergone proper validation. METHOD: A systematic bibliographical review was conducted, based on a search of 14 databases in four languages using the keywords pressure ulcer or pressure sore or decubitus ulcer and risk assessment. Reports of clinical trials or prospective studies of validation were included in the review. FINDINGS: Thirty-three studies were included in the review, three on clinical effectiveness and the rest on scale validation. There is no decrease in pressure ulcer incidence was found which might be attributed to use of an assessment scale. However, the use of scales increases the intensity and effectiveness of prevention interventions. The Braden Scale shows optimal validation and the best sensitivity/specificity balance (57.1%/67.5%, respectively); its score is a good pressure ulcer risk predictor (odds ratio = 4.08, CI 95% = 2.56-6.48). The Norton Scale has reasonable scores for sensitivity (46.8%), specificity (61.8%) and risk prediction (OR = 2.16, CI 95% = 1.03-4.54). The Waterlow Scale offers a high sensitivity score (82.4%), but low specificity (27.4%); with a good risk prediction score (OR = 2.05, CI 95% = 1.11-3.76). Nurses' clinical judgement (only considered in three studies) gives moderate scores for sensitivity (50.6%) and specificity (60.1%), but is not a good pressure ulcer risk predictor (OR = 1.69, CI 95% = 0.76-3.75). CONCLUSION: There is no evidence that the use of risk assessment scales decreases pressure ulcer incidence. The Braden Scale offers the best balance between sensitivity and specificity and the best risk estimate. Both the Braden and Norton Scales are more accurate than nurses' clinical judgement in predicting pressure ulcer risk.     

自制神经外科压疮危险因素评估量表与Braden量表信度与效度的比较研究

目的 更准确地评估神经外科患者发生压疮的危险性,降低压疮发生率.方法 采用两个评估量表(即自制神经外科压疮危险因素评估量表和Braden量表)评估500例神经外科患者的压疮危险因素,并进行信度和效度的比较.结果 自制神经外科压疮危险因素评估量表的Cronbach's α为0.941,Braden量表的Cronbach's α为0.743.因子分析结果显示,两个量表的结构效度与原设想的基本一致.预测效度显示,当自制神经外科压疮危险因素评估量表的诊断界值取16分时,灵敏度和特异度分别为89%和78%;当Braden量表取18分时,灵敏度和特异度分别为78%和58%.结论 两种量表均具有较好的内部一致性信度、结构效度和预测效度,但自制神经外科压疮危险因素评估量表优于Braden量表,是适合神经外科患者人群的压疮危险评估工具.     

Development of a new risk assessment scale for predicting pressure ulcers in an intensive care unit

Aims and objectives: The study aimed to evaluate the predictive validity and accuracy of a new pressure ulcer risk assessment scale in two Indonesia intensive care units (ICUs). Background: Several risk assessment scales have been designed to identify patients at risk of developing pressure ulcers in ICU. However, the relative weight of each variable that contributes to pressure ulcer development in these scales is not described to enable designing of a risk assessment scale. Currently, the risk factors contributing to pressure ulcer development include interface pressure, body temperature and cigarette smoking. Design: A prospective cohort study was conducted in two ICUs in Pontianak, Indonesia. Methods: A total of 253 patients were recruited to the study from both hospitals. Data collection included new risk assessment scale [i.e. the Suriadi and Sanada (S.S.) scale] scoring, demographic, pressure ulcer severity scores (based on the National Pressure Ulcer Advisory Panel) and skin condition measures. Using the S.S. scale, trained data collectors scored patients once and assessed the body temperature daily until patients were discharged. Additionally, daily data were also collected in relation to the patient‘s skin condition and stage of pressure ulcer. Results: Out of the 253 patients, 72 (28·4%) developed pressure ulcers. In ICU A, the incidence was 27%; pressure ulcers developed into stage I (41·7%), stage II (45·8%), stage III (10·4%) and stage IV (2·1%). In ICU B, the incidence was 31·6%; the development of pressure ulcers was 48% in stage I and 52% in stage II. Using the predictive validity test, the S.S. scale balanced sensitivity (81%) and specificity (83%) at a cut‐off score of 4. The area under the receiver‐operating characteristic curve was 0·888 (confidence interval: 0·84–0·93). Conclusion: The S.S. scale was found to be a valid risk assessment tool to identify the patients at risk of developing pressure ulcers in Indonesia ICU.     

Pressure ulcers: validation of two risk assessment scales

Aims and objectives. To compare the predictive value of two pressure ulcer risk assessment scales (Braden and Norton) and of clinical judgement. To evaluate the impact of effective preventive measures on the predictive validity of the two risk assessment scales. Methods. Of the 1772 participating older patients, 314 were randomly selected and assigned to the ‘turning’ group; 1458 patients were assigned to the ‘non‐turning’ group. Using the Braden and the Norton scale the pressure ulcer risk was scored twice weekly during a four‐week period. Clinical assessment was monitored daily. The patients at risk in the ‘turning’ group (Braden score <17 or Norton score <12) were randomly assigned to a two‐hour turning schedule or to a four‐hour turning schedule in combination with a pressure‐reducing mattress. The ‘non‐turning’ group received preventive care based on the clinical judgement of the nurses. Results. The diagnostic accuracy was similar for both scales. If nurses act according to risk assessment scales, 80% of the patients would unnecessarily receive preventive measures. The use of effective preventive measures decreased the predictive value of the risk assessment scales. Nurses predicted pressure ulcer development less well than the Braden and the Norton scale. Only activity, sensory perception, skin condition and existence of old pressure ulcers were significant predictors of pressure ulcer lesions. Relevance to clinical practice. The effectiveness of the Norton and Braden scales is very low. Much needless work is done and expensive material is wrongly allocated. The use of effective preventive measures decreases the predictive value of the risk assessment scales. Although the performance of the risk assessment scales is poor, using a risk assessment tool seems to be a better alternative than relying on the clinical judgement of the nurses.     

Inter-rater reliability and Waterlow's pressure ulcer risk assessment tool

AIM: To ascertain whether a lack of inter-rater reliability with the original Waterlow (1996) pressure ulcer risk assessment scale is due to different perceptions of patients by nurses or different interpretations of Waterlow as a tool. METHOD: A sample of 110 qualified nurses, who used the Waterlow pressure ulcer risk assessment scale in their daily work and were delegates at five study days, were given a case study and an uncompleted copy of the tool. They were asked to complete a risk assessment for the patient. The risk assessment score obtained by delegates was analysed using the Wilcoxon Signed Rank Test to measure the null hypothesis that there is no significant difference between the median of the nurses' scores and the patient's actual or 'gold standard' score. RESULTS: Nurses tend to over-rate (n=72, 65 per cent) rather than under-rate (n=25, 23 per cent) the patient's risk of developing a pressure ulcer. Only 13 of the 110 nurses (12 per cent) accurately rated the patient's score as 18. The Wilcoxon Test rejected the null hypothesis that there was no difference in the risk scores arrived at by individual nurses and the patient's actual score, that is, there is a significant difference between the scores obtained by the nurses in the study and the gold standard score. CONCLUSION: The results show poor inter-rater reliability when using the Waterlow pressure ulcer risk assessment scale. Part of the problem is that nurses are not using the tool in the way it was intended.     

Predictive risk scales for development of pressure ulcers in pediatric patients admitted to general ward and intensive care unit

BACKGROUNDMore than ten special scales are available to predict the risk of pressure ulcers in children. However, the performances of those scales have not yet been compared in China. AIMTo compare the Waterlow, Braden Q, and Glamorgan scales, and identify more suitable pressure ulcer evaluation scale for the pediatric intensive care unit (PICU).METHODSTrained nurses used the Waterlow, Braden Q, and Glamorgan scales to assess pediatric patients at Sun Yat-sen Memorial Hospital (China) within 24 h of admission from May 2017 to December 2020 in two stages. Skin examination was carried out to identify pressure ulcers every 3 d for 3 wk. RESULTSThe incidence of pressure ulcers was 3/28 (10.7%) in the PICU and 5/314 (1.6%) in the general pediatric ward. For children in the general ward, the Waterlow, Braden Q, and Glamorgan scales had comparable area under the operating characteristic curve (AUC) of 0.870, 0.924, and 0.923, respectively, and optimal cut-off values of 14, 14, and 29 points. For PICU, the Waterlow, Braden Q, and Glamorgan scales had slightly lower AUC of 0.833, 0.733, and 0.800, respectively, and optimal cut-off values of 13, 16, and 27 points. Braden Q demonstrated a satisfactory specificity, and during the second stage of the study for PICU patients, the AUC of the Braden Q scale was 0.810, with an optimal cut-off value of 18.35 points.CONCLUSIONThe Waterlow, Braden Q, and Glamorgan scales have comparable performance, while the Braden Q scale demonstrates a better specificity and can be successfully used by pediatric nurses to identify patients at high risk of pressure ulcers in PICU.     

Validity of pressure ulcer risk assessment scales; Cubbin and Jackson, Braden, and Douglas scale

This study was to compare the validity of three pressure ulcer risk tools: Cubbin and Jackson, Braden, and Douglas scales. Data were collected three times per week from 48 to 72 h after admission based on the three pressure ulcer risk assessment scales and skin assessment tool developed by the Panel for the Prediction and Prevention of Pressure Ulcers (1994) from 112 intensive care unit (ICU) patients in a educational hospital Ulsan, Korea during December 11, 2000 to February 10, 2001. When a patient developed a pressure ulcer at the time of assessment, the patient was classified into 'pressure ulcer group', and when patients did not have a pressure ulcer until they died, moved to other wards or were discharged from the hospital, they were classified into 'not pressure ulcer group'. Four indices of validity and area under the curves (AUC) of receiver operating characteristic (ROC) were calculated. Based on the cut-off point presented by the developer, sensitivity, specificity, positive predictive value, negative predictive value were as follows: Cubbin and Jackson scale: 89%, 61%, 51%, 92%, respectively, Braden scale: 97%, 26%, 37%, 95%, respectively, and Douglas scale: 100%, 18%, 34%, 100%, respectively. AUCs of ROC curve were 0.826 for Cubbin and Jackson, 0.707 for Braden, and 0.791 for Douglas. Overall, the Cubbin and Jackson scale showed the best validity among scales tested and we recommended it for this ICU.     

An evaluation of the Waterlow pressure ulcer risk-assessment tool

The National Institute for Clinical Excellence (NICE, 2001) stated that in order to achieve clinical governance strategies, risk management in the form of pressure ulcer risk assessment will contribute to improved quality of patient care. Risk-assessment tools must display high-predictive values, be highly sensitive and specific, reliable, and easy and convenient to use. Despite their extensively documented poor performance, pressure ulcer risk-assessment scales play a primary role in the prevention and management of pressure ulcers. The tools attempt to determine patients' risk status by quantifying a range of the most commonly recognized risk factors. Although there are over 40 different assessment tools, the Waterlow pressure ulcer risk-assessment tool is the tool that is most widely used in the UK. This article aims to review studies relating to the reliability, content validity, predictive validity, concurrent validity and the construct validity of the Waterlow pressure ulcer risk-assessment tool.     

3种压疮危险评估量表在老年患者中应用的信效度研究

目的 比较和评价Norton、Braden和Waterlow 3种压疮危险评估量表在老年患者中应用的信效度.方法 选取某三级甲等医院老年患者271例,运用3种量表连续评估患者的压疮危险,以Cronbach's α系数、内容效度指数、因子分析、ROC曲线等方法评价和比较各量表的信效度.结果Norton、Braden、Watedow量表的内部一致性信度分别为0.71、0.79、0.32;内容效度指数分别为0.85、0.91、0.87;因子分析得到的方差累计贡献率分别为71.73%、70.34%、65.76%;灵敏度和特异度分别为(0.75、0.62)、(0.74、0.59)、(0.86、0.59).结论 Waterlow量表的内部一致性信度低,但预测能力最好;Braden量表的信效度均高,但预测能力偏低.     

Immobility--a major risk factor for development of pressure ulcers among adult hospitalized patients: a prospective study

OBJECTIVE: To identify risk factors associated with pressure ulcer development among adult hospitalized medical and surgical patients. DESIGN: A prospective comparative study including 530 adult patients from medical and surgical wards. Registered Nurses made the data collection on admission and once a week for up to 12 weeks. The risk assessment scale used was the Risk Assessment Pressure Sore (RAPS) scale, including the following variables; general physical condition, activity, mobility, moisture, food intake, fluid intake, sensory perception, friction and shear, body temperature and serum albumin. RESULTS: Sixty-two (11.7%) patients developed 85 pressure ulcers. The most common pressure ulcer was that of nonblanchable erythema. Patients who developed pressure ulcers were significantly older, hospitalized for a longer time, had lower scores on the total RAPS scale, had lower weight and lower diastolic blood pressure than nonpressure ulcer patients did. In the multiple logistic regression analyses using variables included in the RAPS scale immobility emerged as a strong risk factor. When adding remaining significant variables in the analyses, mobility, time of hospitalization, age, surgical treatment and weight were found to be risk factors for pressure ulcer development. CONCLUSION: It is confirmed that immobility is a risk factor of major importance for pressure ulcer development among adult hospitalized patients. The results also indicate that the RAPS scale may be useful for prediction of pressure ulcer development in clinical practice.     

Validation of pressure ulcer risk assessment scales: a critique

AIM: The aim of this paper is to present critical analysis of the validation methods of pressure ulcer risk assessment scales. BACKGROUND: The validation of pressure ulcer risk assessment scales remains a topic of considerable debate and uncertainty. The Braden scale and Norton scale are the most frequently used. Sensitivity and specificity are the recommended and most commonly used epidemiological tools to evaluate the validity of those risk assessment scales. DISCUSSION: The use of preventive measures influences both the sensitivity and specificity of the scales. Analysis of published studies on risk assessment scales reveals that, although some patients received preventive measures and others did not, this was not taken into account. Consequently, generalization of those results is not possible. Some possible alternative designs for studying the validity of risk assessment scales are discussed. CONCLUSIONS: Currently available risk assessment scales are of only limited value, and there use will result in many patients being falsely identified as at risk or not at risk. Sensitivity and specificity criteria are not the most appropriate tools to validate risk assessment scales. A risk assessment scale should be evaluated in combination with the preventive measures used.     

Pressure ulcer risk assessment in critical care: Interrater reliability and validity studies of the Braden and Waterlow scales and subjective ratings in two intensive care units

Background

The application of standardized pressure ulcer risk assessment scales is recommended in clinical practice.

Objectives

The aims of this study were to compare the interrater reliabilities of the Braden and Waterlow scores and subjective pressure ulcer risk assessment and to determine the construct validity of these three assessment approaches.

Design

Observational.

Settings

Two intensive care units of a large University Hospital in Germany.

Participants

21 and 24 patients were assessed by 53 nurses. Patients’ mean age was 69.7 (SD 8.3) and 67.2 (SD 11.3).

Methods

Two interrater reliability studies were conducted. Samples of patients were assessed independently by a sample of three nurses. A 10-cm visual analogue scale was applied to measure subjective pressure ulcer risk rating. Intraclass correlation coefficients (ICC) and standard errors of measurement (SEM) were used to determine interrater reliability and agreement of the item and sum scores. Pearson product moment correlation coefficients (r) were used to indicate the degree and direction of the relationships between the measures.

Results

The interrater reliability for the subjective pressure ulcer risk assessment was ICC(1,1) = 0.51 (95% CI 0.26-0.74) and 0.71 (95% CI 0.53-0.85). Interrater reliability of Braden scale sum scores was ICC(1,1) = 0.72 (95% CI 0.52-0.87) and 0.84 (95% CI 0.72-0.92) and for Waterlow scale sum scores ICC(1,1) = 0.36 (95% CI 0.09-0.63) and 0.51 (95% CI 0.27-0.72). The absolute degree of correlation between the measures ranged from 0.51 to 0.77.

Conclusions

Interrater reliability coefficients indicate a high degree of measurement error inherent in the scores. Compared to subjective risk assessment and the Waterlow scale scores the Braden scale performed best. However, measurement error is too high to draw valid inferences for individuals. Less than 26-59% of variances in scores of one scale were determined by scores of another scale indicating that all three instruments only partly measured the same construct. The use of the Braden-, Waterlow- and Visual Analogue scales for measuring pressure ulcer risk of intensive care unit patients is not recommended.     

Predicting pressure ulcer risk: a multifactorial approach to assess risk factors in a large university hospital population

Aims. The purpose of this study was: (1) to determine the combination of risk factors which best predicts the risk of developing pressure ulcers among inpatients in an acute care university hospital; (2) to determine the appropriate weight for each risk factor; and (3) to derive a concise and easy‐to‐use risk assessment tool for daily use by nursing staff. Background. Efficient application of preventive measures against pressure ulcers requires the identification of patients at risk. Adequate risk assessment tools are still needed because the predictive value of existing tools is sometimes unsatisfactory. Design. Survey. Methods. A sample of 34,238 cases admitted to Essen University Clinics from April 2003 and discharged up to and including March 2004, was enrolled into the study. Nursing staff recorded data on pressure ulcer status and potential risk factors on admission. Predictors were identified and weighted by multivariate logistic regression. We derived a risk assessment scale from the final logistic regression model by assigning point values to each predictor according to its individual weight. Results. The period prevalence rate of pressure ulcers was 1·8% (625 cases). The analysis identified 12 predictors for developing pressure ulcers. With the optimum cut‐off point sensitivity and specificity were 83·4 and 83·1%, respectively, with a positive predictive value of 8·4% and a negative predictive value of 99·6%. The diagnostic probabilities of the derived scale were similar to those of the original regression model. Conclusions. The predictors mostly correspond to those used in established scales, although the use of weighted factors is a partly novel approach. Both the final regression model and the derived scale show good prognostic validity. Relevance to clinical practice. The derived risk assessment scale is an easy‐to‐understand, easy‐to‐use tool with good prognostic validity and can assist in effective application of preventive measures against pressure ulcer.     

The Development of a Pressure Ulcer Risk-Assessment Scale for Perioperative Patients

The high incidence of pressure ulcer development in patients in the perioperative setting indicates the need for improved risk assessment and the use of preventive measures. A clinical nurse specialist used Dever's Epidemiological Model as the theoretical framework to develop a perioperative pressure ulcer risk-assessment scale. The risk factors for the scale were based on findings from a review of the literature. The scale, along with a demographic questionnaire and an evaluation form, was distributed to 12 nurses and three anesthesiologists to obtain expert opinion to further the design of the scale. Twelve participants returned the forms. Only four of the participants had previous experience with a pressure ulcer risk-assessment scale. The results indicated that diabetes should be included as a risk factor category and that preexisting skin ulcerations, breakdowns, and conditions should be addressed within the scale. The participants unanimously agreed that moisture is an important factor to assess. Validation of each risk factor is essential to improve the reliability of the scale before its implementation.     

Pressure ulcer risk assessment immediately after cardiac surgery – does it make a difference? A comparison of three pressure ulcer risk assessment instruments within a cardiac surgery population

The intensive care unit (ICU) population has a high risk of developing pressure ulcers. According to several national expert guidelines for pressure ulcer prevention, a risk assessment for every situation in which the patient's condition is changing should be performed using a standardized risk assessment instrument. The aims of this study were to (a) assess the number of patients who are 'at risk' for the development of pressure ulcer according to three commonly used risk assessment instruments in the intermediate period after cardiac surgery procedures, (b) assess which instrument best fits the situation of the ICU patients and c) decide if 'static' risk assessment with an instrument should be recommended. The modified Norton scale, the Braden scale and the 4-factor model were used in a convenience sample of 53 patients to assess the risk for development of pressure ulcer in the first 5 days (in ICU) after cardiac surgery procedures. The number of patients at risk were >60% by the 4-factor model, >70% by the modified Norton scale and >80% by the Braden scale. Sensitivity and specificity in all scales were not satisfactory. Forty-nine per cent (n= 26) of the patients developed a pressure ulcer in the operating room, 13% (n= 7) up to day 5 in the cardiac surgery ICU. Only 1.9% (n= 1) of the pressure ulcers were stage 2. The study concluded that the patients in the cardiac surgery ICU can be identified as at risk during the first 5 days after surgical procedure without continuously using a standardized risk assessment instrument in every changing condition. Individual risk assessment by a standardized risk assessment instrument is only recommended to enable initiation of preventive measures based on patient-specific risk factors.     

Validity of the Waterlow scale for pressure ulcer risk assessment in the intensive care unit: a prospective analysis of 698 patients

Critically ill patients are at a particular risk for developing pressure ulcers. Yet until now, no sufficiently specific, validated pressure ulcer risk assessment instruments exist for critically ill patients. In a prospective study of 698 patients of medical intensive care unit (ICU), we therefore analyzed if the Waterlow scale is suitable for pressure ulcer risk assessment in the ICU. Only patients with no pressure ulcer on admission to the ICU were included. The Waterlow scale was used to assess pressure ulcer risk on admission to the ICU, and the number of points on the scale were analyzed with regard to pressure ulcers development in the course of the ICU stay (121 patients). Our results show that adequate pressure ulcer risk assessment on admission to the ICU is not possible with the Waterlow scale. Sensitivity and specificity reached their maximal values of 64.6% and 48.8%, respectively, at a comparably high cut-off of 30 points on the Waterlow scale (positive and negative likelihood ratio being 1.26 and 0.73, respectively). The area under the curve (AUC) was 0.59 in the receiver-operator-characteristic curve. Adding intensive care related parameters to the scale yielded some degree of improvement (AUC 0.69), but the development of ICU specific pressure ulcer risk scales still seems to be necessary to allow reliable pressure ulcer risk assessment in the ICU.     

Pressure ulcers in palliative care: development of a hospice pressure ulcer risk assessment scale

The aim of this study was to construct a pressure ulcer risk assessment scale appropriate for palliative care patients. Risk assessments were performed using the modified Norton scale and nine newly constructed scales, consisting of the modified Norton scale with various changes. Data were collected from 98 patients in a Swedish hospice between April 1999 and September 2000. Pressure ulcer occurrence was registered weekly in the patient record. Increasing age, male gender, physical inactivity, immobility, decreasing food and fluid intake, incontinence, poor general physical condition and lean body constitution were shown to be significant risk factors for development of pressure ulcers in terminally ill cancer patients. After further testing of the data, one scale was found to be superior in identifying patients at risk, with higher validity than the modified Norton scale. The assessment items in this new scale, The Hospice Pressure Ulcer Risk Assessment Scale (in Swedish: Hospice Riskbed?ming Trycks?r, (HoRT)), are physical activity, mobility and age.     

The impact of pressure ulcer risk assessment on patient outcomes among hospitalised patients

Aims and objectives. To determine whether use of a risk assessment scale reduces nosocomial pressure ulcers. Background. There is contradictory evidence concerning the validity of risk assessment scales. The interaction of education, clinical judgement and use of risk assessment scales has not been fully explored. It is not known which of these is most important, nor whether combining them results in better patient care. Design. Pretest–posttest comparison. Methods. A risk assessment scale namely the Braden was implemented in a group of wards after appropriate education and training of staff in addition to mandatory wound care study days. Another group of staff received the same education programme but did not implement the risk assessment scale and a third group carried on with mandatory study days only. Results. Nosocomial Pressure Ulcer was reduced in all three groups, but the group that implemented the risk assessment scale showed no significant additional improvement. Allowing for age, gender, medical speciality, level of risk and other factors did not explain this lack of improvement. Clinical judgement seemed to be used by nurses to identify patients at high risk to implement appropriate risk reduction strategies such as use of pressure relieving beds. Clinical judgement was not significantly different from the risk assessment scale score in terms of risk evaluation. Conclusions. It is questioned whether the routine use of a risk assessment scale is useful in reducing nosocomial pressure ulcer. It is suggested clinical judgement is as effective as a risk assessment scale in terms of assessing risk (though neither show good sensitivity and specificity) and determining appropriate care. Relevance to clinical practice. Clinical judgement may be as effective as employing a risk assessment scale to assess the risk of pressure ulcers. If this were true it would be simpler and release nursing time for other tasks.     

手术患者压力性损伤风险评估工具的多中心测评研究

目的：检验手术患者压力性损伤风险评估工具在多中心临床应用的信效度及预测能力,并与Waterlow量表进行临床应用效果的对比。方法：采用配额抽样方法,选取2020年7月至12月天津市4所三级甲等医院530例全麻手术患者作为研究对象,对手术患者压力性损伤风险评估工具进行信效度检测,并与Waterlow量表进行压力性损伤风险预测能力的比较。结果：手术患者压力性损伤风险评估工具在手术前、手术后2个阶段的Cronbach’s α系数分别为0.809、0.804;平均量表水平的内容效度指数为0.905;旋转变换累积方差贡献率显示,12个条目均在8%左右,有较强的稳定性,特征值>1的条目累积方差贡献率为75.5%;其术前、术后ROC曲线下面积分别为0.722、0.732;Waterlow量表ROC曲线下面积为0.574。结论：手术患者压力性损伤风险评估工具有较好的信效度和预测能力,可有效判断手术患者压力性损伤风险程度,具有手术患者普适性特点,为手术室压力性损伤同质化预防管理奠定了基础。     

Pressure ulcer risk assessment: application of logistic analysis

AIM: The aim of this study was to investigate the relative importance of key factors affecting the likelihood of hospital acquired pressure ulcers, thus offering the groundwork for the development of an empirically-based risk assessment scale. It also evaluated the predictive performance of the underlying empirical model and compared its classification ability with the empirically observed ability of the Waterlow risk assessment scale. BACKGROUND: Pressure ulcers impose a significant burden on patients and carers and demand substantial resources from the health care system. There is, however, a lack of systematic empirical research on which to base the development of risk assessment measurement tools. METHODS: Multivariate statistical methods were applied to data derived from the records of a cross-sectional sample of around 500 randomly selected inpatient episodes drawn from the population of admissions to a single unit in a large acute hospital during a 2-year period (October 1996 to September 1998). Double-checking of a randomly selected 25% sample of the original records and careful screening out of records with incomplete information or inconsistent values was carried out to ensure a high quality sample. Logit analysis was used to investigate the relative contribution of risk factors, such as continence, skin condition, mobility and inter-hospital transfer to the risk of hospital-acquired pressure ulcer occurrence, whilst cross-validation techniques were employed to check the predictive performance of the model. RESULTS: The results suggest that a simplified version of the Waterlow risk assessment tool has satisfactory predictive ability and the potential for further development. CONCLUSIONS: Two main conclusions emerged from this study. First, it is both feasible and worthwhile to pursue improvement in the development of risk assessment tools using statistical methods. Second, locally-determined risk factors will need to be incorporated into the construction of future risk assessment scales.