A risk assessment scale for the prediction of pressure sore development: reliability and validity.

BACKGROUND The ability to assess the risk of a patient developing pressure sores is a major issue in pressure sore prevention. Risk assessment scales should be valid, reliable and easy to use in clinical practice. AIM To develop further a risk assessment scale, for predicting pressure sore development and, in addition, to present the validity and reliability of this scale. METHODS The risk assessment pressure sore (RAPS) scale, includes 12 variables, five from the re-modified Norton scale, three from the Braden scale and three from other research results. Five hundred and thirty patients without pressure sores on admission were included in the study and assessed over a maximum period of 12 weeks. Internal consistency was examined by item analysis and equivalence by interrater reliability. To estimate equivalence, 10 pairs of nurses assessed a total of 116 patients. The underlying dimensions of the scale were examined by factor analysis. The predictive validity was examined by determination of sensitivity, specificity and predictive value. RESULTS Two variables were excluded as a result of low item-item and item-total correlations. The average percentage of agreement and the intraclass correlation between raters were 70% and 0.83, respectively. The factor analysis gave three factors, with a total variance explained of 65.1%. Sensitivity, specificity and predictive value were high among patients at medical and infection wards. CONCLUSION The RAPS scale is a reliable scale for predicting pressure sore development. The validity is especially good for patients undergoing treatment in medical wards and wards for infectious diseases. This indicates that the RAPS scale may be useful in clinical practice for these groups of patients. For patients undergoing surgical treatment, further analysis will be performed.