pressure ulcer, risk assessment scales, risk assessment and validity



  1. Gonzalez-Ruiz, Jose M. PhD, RN
  2. Sebastian-Viana, Tomas PhD, RN
  3. Losa-Iglesias, Marta E. PhD, RN
  4. Lema-Lorenzo, Isabel RN
  5. Crespo, Fernando J. Nunez PhD, RN
  6. Martin-Merino, Gema RN
  7. Garcia-Martin, Maria R. MPH, RN
  8. Velayos-Rodriguez, Eva RN
  9. Nogueiras-Quintas, Carmen G. RN


OBJECTIVE: The objective of this article was to determine the most suitable cutoff point (CP) for the Braden Scale and Norton Modified Scale by INSALUD Scale (Norton-MI) in an acute care hospital.


DESIGN: The authors have designed a prospective, descriptive study of patients from their hospital. From December 2008 to March 2009, a nurse collected and recorded adult patient data daily, including the appearance of pressure ulcers.


PATIENTS: Adult patients in medical and surgical wards.


MAIN OUTCOMES MEASURE: The parameters used in both scales are sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), area under curve (AUC) of receiver operating characteristic (ROC).


MAIN RESULTS: In the end, the authors have evaluated a total of 1001 patients and obtained 4486 measurements with both the Norton-MI and the Braden scales. The rates for the recommended CP of the Norton-MI scale (CP 14) are as follows: sensitivity: 67.91% (62.42-73.39), specificity: 78.66% (77.41-79.92), PPV: 18.36%, NPV: 97.20%. Those for Braden (CP 16) are as follows: sensitivity: 65.69% (64.19-75), specificity: 79.62% (78.39-80.85), PPV: 19.43%, NPV: 97.37%. The Norton-MI scale offers an AUC-ROC of 0.828 with a 95% confidence interval of 0.811-0.854, and the Braden Scale presents an AUC-ROC of 0.832 with a 95% confidence interval of 0.807 to 0.849.


CONCLUSION: Both scales show good validity data. If the CP is raised: MI-Norton (CP 15): sensitivity: 77.36 (72.43-82.30), specificity 74.27 (72.94-75.61), PPV: 17.52 (15.42-19.62), NPV: 97.89 (97.38-98.41). The Braden scale with a CP of 17 presents sensitivity: 78.38 (73.52-83.24), specificity: 73.44 (72.09-74.79), PPV: 17.25 (15.19-19.31), NPV: 97.96 (97.45-98.47). These CPs improved the predictive capacity of both scales in the authors' hospital environment.