• Used to describe the severity of pressure ulcers.
  • Derived from previously published UK scales developed by a consensus panel of national tissue viability experts.
  • This observational scale has 5 stages ranging from stage 0 to stage 4, where:
    • 0 – No clinical evidence of a pressure sore.
    • 1 – Discoloration of the intact skin.
    • 2 – Partial-thickness skin loss or damage involving epidermis and/or dermis.
    • 3 – Full-thickness skin loss involving damage or necrosis of subcutaneous tissue but not extending to underlying bone, tendon or joint capsule.
    • 4 – Full-thickness skin loss with extensive destruction and tissue necrosis extending to bone, tendon or capsule.
  • The scale has several variations, with the most common being the 1 and 2-digit scales, where the nature and severity of the ulcer are graded.

Clinical Considerations

  • Observational pressure ulcer grading scales are open to bias and subjectivity resulting from individual interpretations. These interpretations reflect clinician knowledge and ability to identify anatomical structures and changes.
  • The Stirling scale is easy to use, has good ulcer description, and good choice of descriptors. The descriptors in the 2-digit version enable a more accurate grading in comparison to other pressure ulcer severity scales. However, because the stage 1 descriptor of the scale focuses on skin discoloration, the validity of the Stirling scale is questionable when used with dark-skinned patients as this criteria may be masked by the skin pigment.

ICF Domain

Body Function ▶ Functions of the Skin


  • Clinician-administered.
  • Using the 1-digit scale, raters indicate the severity of the ulcer from 0 to 4, according to the stage definitions.
  • Using the 2-digit scale, raters indicate the severity of the ulcer according to the stage definitions and specific descriptors.
    • For example, for stage 0 there are three descriptors, 0.1 – normal appearance, intact skin; 0.2 – healed with scarring, and 0.3 – tissue damage, but not assessed as a pressure sore.

Number of Items





  • The scale has 5 stages (0-4), where zero represents no clinical appearance and four indicates full thickness skin loss with extensive destruction extending to bone, tendon or joint capsule.
  • The two digit version includes more detailed ulcer descriptors.



Training Required

Traning is required.


Can be found here.

# of studies reporting psychometric properties: 1


  • Differentiation between the grade descriptors depends on clinical identification of the tissues. Differentiation requires not only observing the wound bed, but also having sufficient knowledge to distinguish the different tissue layers.
  • The higher the grade of the ulcer, the greater the severity of the ulcer.
  • Published data for the SCI population is available for comparison (see Interpretability section of the Study Details sheet).

MCID: not established in SCI
SEM: not established in SCI
MDC: not established in SCI


No values were reported for the reliability of the Stirling’s Ulcer Severity Scale for the SCI population.


  • When the scales were treated as continuous variables, there were significant and low correlations between the Stirling scores and both the Norton (Spearman’s r = -0.28) and the Waterlow scores (Spearman’s r = 0.38), but not the Braden scores.
  • When the scales were treated as categorical variables (at risk, high risk, very high risk), only the Waterlow scores were significantly correlated to the Stirling scores (Spearman’s r = 0.32).

(Wellard 2000)


No values were reported for the responsiveness of the Stirling’s Ulcer Severity Scale for the SCI population.

Floor/Ceiling Effect

No values were reported for the presence of floor/ceiling effects in the Stirling’s Ulcer Severity Scale for the SCI population.


Dr. Vanessa Noonan, Marzena Zhou, Risa Fox

Date Last Updated

3 August 2020

Pedley GE. Comparison of pressure ulcer grading scales: a study of clinical utility and inter-rater reliability. International Journal of Nursing Studies 2004;41:129-140. http://www.ncbi.nlm.nih.gov/pubmed/14725777

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. http://www.ncbi.nlm.nih.gov/pubmed/11855004