We also examined the content coverage provided by the three coding systems (i.e., SNOMED CT, ICF, and ICNP) for the entire MDS. This was necessary given the emphasis of the domain experts and ACOVE indicators on the identification of a range of factors beyond the occurrence of the pain, pressure ulcers, and urinary incontinence (e.g., risk factors, nonspecific signs and symptoms, and processes of care). That is, the MDS data elements used for QI and QM estimates are a subset of the entire MDS and only concern the presence of these conditions. Since the ACOVE indicators and the domain experts recommend considering factors beyond just the presence of the condition as an indicator of quality, we needed to examine the extent to which: (i) each of the three terminology coding systems provided content coverage of the entire MDS; and (ii) the entire MDS provided content coverage relevant to the ACOVE indicators and domain expert indicators.
This required that we carefully consider the way the structure of the MDS document because interpreting the meaning of specific data elements is tightly coupled to the hierarchy, or headings under which that item occurs in the document.
The MDS is organized into 18 sections, with a varying number of items in each section that specify a focused type of assessment.
- Section A: Identification Information, Demographic Information, Customary Routine, and Face Sheet Signatures
- Section B: Cognitive Patterns
- Section C: Communication/Hearing Patterns
- Section D: Vision Patterns
- Section E: Mood and Behavior Patterns
- Section F: Psychosocial Well-being
- Section G: Physical Functioning and Structural Problems
- Section H: Incontinence in Last 14 Days
- Section I: Disease Diagnoses
- Section J: Health Conditions
- Section K: Oral/Nutritional Status
- Section L: Oral/Dental Status
- Section M: Skin Condition
- Section N: Activity Pursuit Patterns
- Section O: Medications
- Section P: Special Treatments and Procedures
- Section Q: Discharge Potential and Overall Status
- Section R: Assessment Information
The MDS data elements that are actually encoded and stored are selected from pick-lists of responses to a number of items or questions within each of these sections. Many sections of the MDS are further subdivided with sub-headings that organize specific items.
For example, Section G: Physical Functioning and Structural Problems specifies a sub-heading of "bed mobility" which is defined as "how resident moves to and from lying position, turns side to side, and positions body when in bed". The person completing the MDS form then records a value of 0, 1, 2, 3, 4, or 8 to describe the resident's overall self-performance of bed mobility and a value of 0, 1, 2, 3, or 8 to indicate the support provided the resident in bed mobility. To completely express the meaning of the concepts, it is necessary to consider the text that explains the numeric coded value in association with the item, the sub-heading, and the section heading.
Another example is the concept of "weight change". The term "weight change" is a sub-heading with the section of "oral/nutritional status". A response of No or Yes is required for two separate items within this sub-heading. One item is "weight loss -- 5% or more in last 30 days or 10% or more in last 180 days" and the other item is "weight gain -- 5% or more in the last 30 days or 10% or more in the last 180 days". In another section of the MDS, "health conditions", there is a sub-heading of "problem conditions", and a list of four items that are "indicators of fluid status". One of those items is "weight gain or loss of 3 or more pounds within a 7 day period". The person completing the form is instructed to check the associated data field if this applies. In the first example, the meaning of the MDS weight change item is related to nutritional status, while in the second example the meaning is related to conditions associated with fluid balance concerns, such as congestive heart failure. The point is that the terms that define the structure of the document contribute to the meaning or semantics of the data elements. These must be made explicit in computer based applications that process the meaning of coded data elements. The coded data elements of Yes or No do not carry any meaning related to the intent of the items with which they are associated.
The overall point to be made is that in order to complete a study of the extent to which various terminology systems provide content coverage for the MDS, it was necessary to include all of the terms in items, sub-headings, and sections that provide the context and meaning of a given data elements. Given that an intent of the study was to determine the content coverage of concepts within the MDS, all terms used within the MDS to label section headings, focused areas of assessment, and data elements were included. Duplicates were removed (e.g., "independent" was only included once). This resulted in a sample of 639 unique terms from the MDS. See Appendix F for a complete listing of these terms.