The Waterlow scale (Waterlow 1985) is a tool used to assess the risk for pressure ulcer development. It was created to provide better sensitivity and specificity than the Norton by increasing the number of items used (Wellard & Lo 2000). Every patient is evaluated on: 1 ) age, 2) sex, 3) body build, 4)appetite, 5) continence of urine and feces, 6) mobility, 7) skin appearance in risk areas and (8) special risks (disorders associated with tissue malnutrition, neurological deficits, medication, recent surgery or trauma).

Number of items: 8

Procedure/Administrator: Raters indicate client status based on personal knowledge of the client or chart review. Items are scored as either dichotomous (yes/no) or on domain specific scales that range from 0-1 to 3-5. Domains are scored based on descriptive criteria provided on the scoring sheet (for example, ‘body build’: average – 0; above average – 1; obese – 2; below average - 3). 

How scored: Scores are totaled to produce a summary score from 3 (best prognosis) to 45 (worst prognosis).

Interpretability: Interpreting scores is difficult given lack of detail in item descriptions. Scores of 10+ denote risk of developing a pressure ulcer, 15+ high risk and 20+ very high risk. No rationale is provided for how these numbers were determined. 

Acceptability: The scale omits items previously found to be important predictors of pressure ulcer development for people with SCI in acute and rehabilitation settings. The reliability of the scale has not been demonstrated with a SCI population, but poor inter-rater reliability has been reported in other populations.

Languages: N/a

Usability: The scale is easy to score and administrate with no patient burden.

Time to administer: 5-10 minutes

Time to score: N/a

Training required: None

Availability: N/a

Equipment required: N/a

Clinical Summary: The Waterlow scale is quick and easy to use screen that provides predictive information about the risk of developing a pressure sore. 

Psychometric Summary:








Inter O: Red light

AUC: Yellow light



Note: TR= Test re-test; IC= Internal Consistency; Inter-O= Inter-observer; Intra-O= Intra-observer; SS= Sensitivity/Specificity; AUC=area under curve

Red light= A single study involving SCI subjects which has less than adequate findings of reliability, validity, and/or responsiveness.

Yellow light= A single study involving subjects with SCI which has adequate to excellent findings of reliability, validity, and/or responsiveness.

Green light= At least 2 studies involving subjects with SCI which have adequate to excellent findings of reliability, validity, and/or responsiveness.

N/a= No information.


  • Ash D. An exploration of the occurrence of pressure ulcers in a British spinal injuries unit. J Clin Nurs 2002;11:470-478.
  • Kelly J. Inter-rater reliability and Waterlow’s pressure ulcer risk assessment tool. Nursing Standard 2005;19:86-87,90-92.
  • Salzberg CA, Byrne DW, Kabir R, van Niewerburg P, Cayten CG. Predicting pressure ulcers during initial hospitalization for acute spinal cord injury. Wounds 1999;11:45-57.
  • Salzberg C A, Byrne DW, Cayten CG, van Niewerburgh P, Murphy JG, Viehbeck M. A new pressure ulcer risk assessment scale for individuals with spinal cord injury. Am J Phys Med Rehabil 1996;75:96-104.
  • Waterlow JJ. Pressure sores: a risk assessment card. Nurs Times1985;81:49-55.
  • Wellard S, Lo SK. Comparing Norton, Braden and Waterlow risk assessment scales for pressure ulcers in spinal cord injuries. Contemp Nurse 2000;9:155-160.