Controversies in classifying and assessing grade 1 pressure ulcers.

Disagreement on how to assess grade 1 pressure ulcers has partly come about because there is no national grading system. There is debate about whether grade 1 ulcers are characterised by blanching or non-blanching erythema, whether damage starts at the epidermis or deeper at the interface of soft tissue and bone, and whether grade 1 ulcers are reversible. Purple ulcers are sometimes considered grade 1 tissue damage when, in fact, they signify full thickness skin loss. A review of the evidence can help to clarify the matter.