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National Healthcare Disparities Report, 2005

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Nursing Home Minimum Data Set (MDS)


U.S. Department of Health and Human Services, Centers for Medicare & Medicaid Services (CMS).

Description/Primary Content

The MDS is the core source of assessment information for the Resident Assessment Instrument (RAI). The MDS is a standardized, primary screening and assessment tool of health status; it measures physical, medical, psychological and social functioning of nursing home residents. The general categories of data and health status items in the MDS include demographics and patient history, cognitive, communication/hearing, vision, and mood/behavior patterns, psychosocial well-being, physical functioning, continence, disease diagnoses, health conditions, medications, nutritional and dental status, skin condition, activity patterns, special treatments and procedures and discharge potential.

Chronic care: refers to those types of patients who enter a nursing facility typically because they are no longer able to care for themselves at home. These patients (or residents) tend to remain in the nursing facility anywhere from several months to several years. The chronic quality measures were calculated on any residents with a full or quarterly MDS assessment in the target quarter.

Post acute care (PAC): refers to those types of patients who are admitted to a facility and typically stay less than 30 days. They are also referred to as "short-stay residents". These admissions typically follow an acute care hospitalization and involve high-intensity rehabilitation or clinically complex care. The post acute measures were calculated on any patients with a 14-day prospective payment system (PPS) MDS assessment in the last six months.

Demographic Data

Gender, age, marital status, race or ethnicity, current payment sources, and health status.

Population Targeted

All residents in Medicare or Medicaid certified nursing and long-term care facilities.

Mode of Administration

Completed by facility personnel, with attestation of accuracy required.

Years Collected

Nursing homes have been collecting MDS since 1990; since June 1998, States have transmitted MDS to the CMS central repository.

Data Collection Schedule

Administered on admission, quarterly, annually, whenever the resident experiences a significant change in status and whenever the facility identifies a significant error in a prior assessment. Also, residents receiving Medicare SNF PPS payment require more frequent assessments (5, 14, 30, 60, 90 day).

Facilities are required to electronically transmit MDS data to the States. The State agencies have the overall responsibility for collecting MDS data in accordance with CMS specifications. The State is also responsible for preparing MDS data for retrieval by a national repository established by CMS.

Geographic Estimates

National, State, facility.

Contact Information

Agency homepage:

Oversight homepage:

Data system homepage:


The nursing home measures were changed in January 2004.

The data were downloaded from in March 2005.

State averages are calculated as a simple average (i.e., unweighted by number of residents) of all the facilities located in the State. Reported rates (i) may be affected by the varying number of facilities for each measure in a State due to minimum denominator sizes (see the Table footnote), and (ii) may not reflect the true rate of incidence within a State because the simple averages can only be interpreted as an average of facility rates.

Risk Adjustment for Measures:Three methods are used for risk adjusting the Nursing Home Care measures which use the MDS. One method is to exclude residents where the outcomes are not under facility control (e.g., the resident has a condition, such as a pressure ulcer, upon admission) or where the outcome may be unavoidable (e.g., the resident has end-stage disease or is comatose). Another method is adjustment based on resident-level covariates that have been found to increase risk for an outcome using logistic regression models. The third method is adjustment using logistic regression models based on a Facility Admission Profile (FAP), or the proportion of residents who enter the facility over the past year already with that outcome.


U.S. Dept. of Health &Human Services, Centers for Medicare & Medicaid Services. National Nursing Home Quality Measures, User's Manual, November, 2004 (V1.2), (consolidation of original User's Manual and Technical User's Manual), available at



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