The Minimum Data Set is a comprehensive assessment tool required of all long-term care facilities that provide care to Medicare patients. Developed in response to mandates in the Omnibus Reconciliation Act of 1989, the tool was created to improve the quality of care in long-term care facilities. In relation to pressure ulcers, the MDS form is intended "to ensure that a resident who enters the facility without a pressure sore does not develop a pressure sore unless the individual's clinical condition demonstrates that [it was] unavoidable" (Health Care Financing Administration Guide to Surveyors of Long-Term Care Facilities). Increasingly, the MDS is being used as a source of data for clinical epidemiological studies. Many long-term care facilities use the MDS as their only tool for assessing pressure ulcer risk.
In January 1996, the original MDS was replaced with the MDS-2 which provides for more extensive assessment of several functional areas including skin condition. Although the revisions were intended to create a more comprehensive tool for assessing residents in long-term care, the modifications made to Section M (skin condition) are clinically inappropriate and incongruent with existing knowledge. First, the definition of pressure ulcer provided in the MDS-2 guide fails to acknowledge all etiologic factors in pressure ulcer development and lacks the specificity to differentiate pressure ulcer injury from other types of injury. Specifically, a pressure ulcer is defined as any lesion caused by pressure resulting in damage to underlying tissue. The implication from this definition is that injuries arising from shear and friction, which frequently interact with pressure in the development of pressure ulcers, would not be considered as pressure ulcers. This represents a more limited definition of a pressure ulcer and is at odds with the definition set forth in the AHCPR Guideline. Furthermore, the MDS-2 definition fails to provide sufficient description of the defining characteristics of a pressure ulcer to permit accurate differentiation of pressure ulcers from other types of injuries, such as diabetic insensate foot ulcers.
Compounding the lack of a clear definition of pressure ulcer on the MDS-2 is the presence of an alternative type of ulcer labeled the stasis ulcer. The MDS-2 defines a stasis ulcer as an ulcer caused by poor circulation in the lower extremity. This contrasts with the usual clinical definition of a stasis ulcer as a wound associated with chronic ambulatory venous hypertension. It is also unclear if MDS-2 definition is intended to include ulcers arising from arterial insufficiency or if this type of chronic wound is not to be included in the assessment of skin condition. The misclassification of ulcers that results from the lack of clarity in distinguishing pressure ulcers and other types of chronic wounds can result in inappropriate citation of facilities for "unavoidable" pressure ulcers and failure of facilities to provide care appropriate to the etiology of the wound.
The method of ulcer staging mandated in the MDS-2 is also problematic. The MDS-2 requires that all ulcers be staged regardless of the etiology. The definitions provided for ulcer stages are similar to the NPUAP staging system except for Stage I ulcer which is defined as a persistent area of skin redness (without a break in the skin) that does not disappear when pressure is relieved. Previous attempts to apply this staging system to venous ulcers have not been successful. Furthermore, alternative systems for grading arterial ulcers and insensate foot ulcers (i.e. Wagner's) are commonly accepted and used in clinical practice. The MDS-2 requirement that all ulcers be staged according to one staging system fails to recognize these well established clinical practices and in so doing creates confusion for practitioners. This is accentuated by the directive in the MDS-2 that eschar-covered ulcers be classified at Stage 4 ulcers until they are debrided rather than considering such ulcers non-stagable, as recommended by the AHCPR Guideline.
The requirement of quarterly assessments with the MDS-2 leads to the potential for pressure ulcers to be restaged. Since a resident's pressure ulcer may persist beyond three months, the mandated quarterly reassessment with the MDS-2 will necessitate describing the ulcer stage at that time. No mechanism exists to document the progression of ulcer healing leaving the practitioner no alternative but to restage the ulcer. This practice violates the intent of a staging system, that is, to define the maximum depth of tissue injury, and has been disavowed by the NPUAP. Furthermore, the structure of this tool prohibits tracking of specific wound outcomes because individual wounds are not identified.
Although the original aim of the MDS was to provide a clinical tool for assessment and planning of care for residents in long-term care, it has been applied to purposes extending far beyond these clinical activities. Since its implementation, the MDS has become a tool for quality assurance, reimbursement, long-term care recertification, and clinical research data bases. Long-term care facilities are increasingly relying on the MDS-2 as a tool for risk assessment. The lack of clarity in definitions and the failure to articulate the MDS-2 assessments with existing knowledge will produce flawed data regarding residents in long-term care and lead to inappropriate decision-making regarding care. It would advance society in general, and the long-term care population in particular, if government agencies such as the Health Care Financing Administration (HCFA) and health care organizations concerned with this patient population, such as the NPUAP, work collaboratively to rectify these problems and create a more clinically valid, meaningful tool.
Taken from the NPUAP Report, a newsletter from the National Pressure Ulcer Advisory
Panel. Vol. 4, No. 3, April, 1996.