Chapter 2. Effectiveness of Care (continued, 4)

National Healthcare Disparities Report, 2011


Functional Status Preservation and Rehabilitation

Importance

Demographics
Noninstitutionalized adults needing help of another person with activities of daily living (ADLs)xxviii (2009)4.4 million (Adams, et al., 2010)
Noninstitutionalized adults needing help with instrumental activities of daily living (IADLs)xxix (2009)53,582 (Kochanek, et al., 2011)
Nursing home residents needing help with ADLs (2004)1.5 million (NCHS, 2004)
Number of Medicare beneficiaries receiving inpatient rehabilitation facility care (2009)361,000 (MedPAC, 2011)
Cost
Medicare payments for outpatient physical therapy (2006 est.)$3.1 billion (Ciolek & Hwang, 2008)
Medicare payments for outpatient occupational therapy (2006 est.)$747 million (Ciolek & Hwang, 2008)
Medicare payments for outpatient speech-language pathology services (2006 est.)$270 million (Ciolek & Hwang, 2008)
Medicare payments for outpatient rehabilitation (2010)$3.8 billion (CMS, 2010a)
Medicare payments for inpatient rehabilitation facility care (2010)$6.4 billion (MedPAC, 2011)

Measures

A person's ability to function can decline with disease or age, but it is not always an inevitable consequence. Threats to function span a wide variety of medical conditions. Services to maximize function are delivered in a variety of settings, including providers' offices, patients' homes, long-term care facilities, and hospitals. Some health care interventions can help prevent diseases that commonly cause declines in functional status. Other interventions, such as physical activity, physical therapy, occupational therapy, and speech-language pathology services, can help patients regain function that has been lost or minimize the rate of decline in functioning.

The NHQR and NHDR track several measures related to functional status preservation and rehabilitation. Two measures are highlighted in this section:

  • Improvement in mobility among home health care patients.
  • Nursing home residents needing more help with daily activities.

In addition, this year we have a special focus section on functional improvement of inpatient rehabilitation facility (IRF) patients recovering from stroke.

Findings

Outcome: Improvement in Mobility Among Home Health Care Patients

After an illness or injury, many patients receiving home health care may need temporary help to walk safely. This assistance can come from another person or from equipment, such as a cane. Patients who use a wheelchair may have difficulty moving around safely, but if they can perform this activity with little assistance, they are more independent, self-confident, and active.

As patients recover from illness or injury, physical therapy can facilitate improvements in walking and moving with a wheelchair. However, in cases of patients with some neurologic conditions, such as progressive multiple sclerosis or Parkinson's disease, ambulation may not improve even when the home health agency provides good care. In addition, the characteristics of patients referred to home health agencies vary across States.

 

Figure 2.51. Adult home health care patients whose ability to walk or move around improved, by race and ethnicity, 2002-2009

Figure 2.51. Adult home health care patients whose ability to walk or move around improved, by race and ethnicity, 2002-2009. For details, go to [D] Text Description below.

Figure 2.51. Adult home health care patients whose ability to walk or move around improved, by race and ethnicity, 2002-2009. For details, go to [D] Text Description below.

[D] Select for Text Description.

Key: AI/AN = American Indian or Alaska Native; NHOPI = Native Hawaiian or Other Pacific Islander.
Source: Centers for Medicare & Medicaid Services, Outcome and Assessment Information Set (OASIS), 2002-2009.
Denominator: Adult nonmaternity patients completing an episode of skilled home health care and not already performing at the highest level at the start of the episode, according to the OASIS question on ambulation.

  • From 2002 to 2009, the percentage of home health care patients who got better at walking or moving around improved for each racial and ethnic group (Figure 2.51).
  • The 2008 top 5 State achievable benchmark was 54%.xxx At the current 5% annual rate of increase, this benchmark could be attained overall in about 4 years.
  • Rates of improvement varied across racial and ethnic groups. Whites could attain the achievable benchmark in about 3 years. Asians and NHOPIs could attain the benchmark sooner than Whites, while Blacks, AI/ANs, multiple-race individuals, and Hispanics would not attain the benchmark for between 5 and 11 years.

Also, in the NHQR:

  • From 2002 to 2009, the percentage of home health care patients who got better at walking or moving around improved for the total population.
Outcome: Nursing Home Residents Needing More Help With Daily Activities

Long-stay residents typically enter a nursing facility because they can no longer care for themselves at home. They tend to remain in the facility for several months or years. While almost all long-stay nursing home residents have limitations in their ADLs, nursing home staff help residents stay as independent as possible.xxxi Most residents want to care for themselves, and the ability to perform daily activities is important to their quality of life. Some functional decline among residents cannot be avoided, but optimal nursing home care seeks to minimize the rate of decline. This measure uses assessments of need for help with daily activities, conducted regularly by nursing homes, to identify those residents whose need for help increased from one assessment to the next.

 

Figure 2.52. Long-stay nursing home residents whose need for help with daily activities increased, by race/ethnicity, 2000-2009

Figure 2.52. Long-stay nursing home residents whose need for help with daily activities increased, by race/ethnicity, 2000-2009. For details, go to [D] Text Description below.

[D] Select for Text Description.

Key: API = Asian or Pacific Islander; AI/AN = American Indian or Alaska Native.
Source: Centers for Medicare & Medicaid Services, Minimum Data Set, 2000-2009. Data are from the third quarter of each calendar year.
Denominator: All long-stay residents in Medicare- or Medicaid-certified nursing home facilities.
Note: For this measure, lower rates are better. White, Black, API, and AI/AN are non-Hispanic groups. Hispanic includes all races.

  • In 2009, 16% of long-stay nursing home residents experienced a decline in their ability to perform daily activities and required increasing assistance (data not shown). Between 2000 and 2009, the rate increased among Blacks (Figure 2.52).
  • In all years, API residents were less likely than White residents to need increased help with daily activities. In all years before 2008, AI/AN and Hispanic residents were also less likely to need increased help with daily activities.
  • The 2008 top 5 State achievable benchmark was 13%.xxxii In 2009, API residents had surpassed the benchmark. However, other racial/ethnic groups did not demonstrate progress toward the benchmark.

Also, in the NHQR:

  • Residents ages 0-64 were less likely to need increasing help with daily activities compared with residents ages 65-74.
New! Focus on Inpatient Rehabilitation Patients

Patients receive rehabilitation therapies for a range of impairments from different types of providers, and a major distinction is whether these services are received on an inpatient or outpatient basis. The method for assessing how a patient improves with receipt of rehabilitation services varies by provider type. Each Medicare-certified IRF collects measures of functional status, called the Functional Independence Measure (FIM), at admission and discharge for each Medicare patient as part of the IRF Patient Assessment Instrument. In addition to providing information on total functional gain between admission and discharge, the FIM has several subscores (e.g., self-care [ADLs], motor function, and social cognition).

Approximately 780,000 people experience a new or recurrent stroke every year, and stroke is the most common reason for inpatient rehabilitation. Nearly a third of stroke patients never regain their ability to walk independently again (American Heart Association, 2008). For stroke patients, we examined FIM motor score gain. We also examined FIM communication score gain, differentiating strokes that affect the left and right sides of the body since they have different effects on communication. We restricted analyses to patients who had initial rehabilitation and were discharged home as a way of controlling for patient case mix.

 

Figure 2.53. Mean locomotion score gain among patients in an inpatient rehabilitation facility for stroke, by race/ethnicity, 2002-2007

Figure 2.53. Mean locomotion score gain among patients in an inpatient rehabilitation facility for stroke, by race/ethnicity, 2002-2007. For details, go to [D] Text Description below.

[D] Select for Text Description.

Source: Centers for Medicare & Medicaid Services, Inpatient Rehabilitation Facility Patient Assessment Instrument, 2002-2007.
Denominator: Medicare patients in an inpatient rehabilitation facility for stroke for initial rehabilitation and discharged home.
Note: White, Black, and Asian are non-Hispanic groups. Hispanic includes all races.

  • From 2002 to 2007, there were no statistically significant changes in mean locomotion score gain (Figure 2.53).
  • In most years, Hispanics experienced smaller locomotion score gains than Whites.

Also, in the NHQR:

  • From 2002 to 2007, patients age 85 and over experienced smaller locomotion score gains than patients ages 65-74.

Figure 2.54. Mean communication score gain among patients in an inpatient rehabilitation facility for stroke, by side of body affected and race/ethnicity, 2002-2007

Figure 2.54. Mean communication score gain among patients in an inpatient rehabilitation facility for stroke, by side of body affected and race/ethnicity, 2002-2007. For details, go to [D] Text Description below.

Figure 2.54. Mean communication score gain among patients in an inpatient rehabilitation facility for stroke, by side of body affected and race/ethnicity, 2002-2007. For details, go to [D] Text Description below.

[D] Select for Text Description.

Source: Centers for Medicare & Medicaid Services, Inpatient Rehabilitation Facility Patient Assessment Instrument, 2002-2007.
Denominator: Medicare patients in an inpatient rehabilitation facility for stroke for initial rehabilitation and discharged home.
Note: White, Black, and Asian are non-Hispanic groups. Hispanic includes all races.

  • Overall, patients with right body strokes experienced larger communication score gains than patients with left body strokes (Figure 2.54).
  • Differences related to race and ethnicity did not meet criteria for significance.

Also, in the NHQR:

  • In 2004 and 2006, patients age 85 and over with right body strokes experienced smaller communication score gains than patients ages 65-74. Age differences among patients with left body strokes did not meet criteria for significance.

 

 

Supportive and Palliative Care

Importance

Demographics
Number of Medicare nursing home residents ever admitted during the calendar year (2009)2.5 million (CMS, 2010b)
Number of Medicare fee-for-service (FFS) home health patientsxxxiii (2009)3.3 million (CMS, 2010c)
Number of Medicare FFS beneficiaries using Medicare hospice services (2009)1.1 million (CMS, 2010d)
Cost
Total costs of nursing home carexxxiv (2009)$137 billion (CMS, 2010b)
Total costs of home health carexxxiv (2009)$68.3 billion (CMS, 2010c)
Medicare FFS payments for hospice services (2009 est.)$12.1 billion (CMS, 2010d)

Measures

Disease cannot always be cured, and functional impairment cannot always be reversed. For patients with long-term health conditions, managing symptoms and preventing complications are important goals. Supportive and palliative care cuts across many medical conditions and is delivered by many health care providers. Supportive and palliative care focuses on enhancing patient comfort and quality of life and preventing and relieving symptoms and complications. Toward the end of life, hospice care provides patients and families with practical, emotional, and spiritual support to help cope with death and bereavement. Honoring patient values and preferences for care is also critical. Palliative and end-of-life care need to be "capable of promising dignity, comfort, companionship, and spiritual support to patients and families facing advanced illness or dying" (National Priorities Partnership, 2008).

The NHQR and NHDR track several measures of supportive and palliative care delivered by home health agencies, nursing homes, and hospices. Five measures are presented in this section:

  • Relief of suffering:
    • Shortness of breath among home health care patients.
    • Pressure sores in nursing home residents.
  • Help with emotional and spiritual needs:
    • Right amount of emotional support among hospice patients.
  • Effective communication:
    • Enough information about what to expect among hospice family caregivers.
  • High-quality palliative care:
    • Care consistent with patient's wishes among hospice patients.

Findings

Relief of Suffering
Outcome: Shortness of Breath Among Home Health Care Patients

Shortness of breath is uncomfortable. Many patients with heart or lung problems experience difficulty breathing and may tire easily or be unable to perform daily activities. Doctors and home health staff should monitor shortness of breath and may give advice, therapy, medication, or oxygen to help lessen this symptom.

 

Figure 2.55. Adult home health care patients who had less shortness of breath between the start and end of a home health care episode, by race and ethnicity, 2002-2009

Figure 2.55. Adult home health care patients who had less shortness of breath between the start and end of a home health care episode, by race and ethnicity, 2002-2009. For details, go to [D] Text Description below.

 Figure 2.55. Adult home health care patients who had less shortness of breath between the start and end of a home health care episode, by race and ethnicity, 2002-2009. For details, go to [D] Text Description below.

[D] Select for Text Description.

Key: NHOPI = Native Hawaiian or Other Pacific Islander; AI/AN = American Indian or Alaska Native.
Source: Centers for Medicare & Medicaid Services, Outcome and Assessment Information Set, 2002-2009.
Denominator: Adult nonmaternity patients completing an episode of skilled home health care.

  • Between 2002 and 2009, the percentage of adult home health care patients who showed improvement in shortness of breath over the course of a home health episode increased for the total population from 53% to 60% (data not shown), as well as for each racial and ethnic group except Hispanics (Figure 2.55).
  • From 2005 to 2009, Hispanics were significantly less likely than non-Hispanic Whites to show improvement in shortness of breath.
  • The 2008 top 5 State achievable benchmark was 68%.xxxv At the current 2% annual rate of increase, this benchmark could be attained overall in about 7 years. Whites, Asians, and NHOPIs could attain the benchmark in under 7 years, while Blacks, AI/ANs, and multiple-race individuals would not attain the benchmark for 10 years. Hispanics show no movement toward the benchmark.

Also, in the NHQR:

  • Between 2002 and 2009, the percentage of adult home health care patients who showed improvement in shortness of breath increased for every age group.
Outcome: Pressure Sores in Nursing Home Residents

A pressure ulcer, or pressure sore, is an area of broken-down skin caused by sitting or lying in one position for an extended time and can be very painful. Residents should be assessed by nursing home staff for presence or risk of developing pressure sores.

Nursing homes can help to prevent or heal pressure sores by keeping residents clean and dry and by changing their position frequently or helping them move around. Other interventions include making sure residents get proper nutrition and using soft padding to reduce pressure on the skin. However, some residents may get pressure sores even when a nursing home provides good preventive care.

 

Figure 2.56. Short-stay (left) and high-risk long-stay (right) nursing home residents with pressure sores, by race/ethnicity, 2000-2009

Figure 2.56. Short-stay (left) and high-risk long-stay (right) nursing home residents with pressure sores, by race/ethnicity, 2000-2009. For details, go to [D] Text Description below.

Figure 2.56. Short-stay (left) and high-risk long-stay (right) nursing home residents with pressure sores, by race/ethnicity, 2000-2009. For details, go to [D] Text Description below.

[D] Select for Text Description.

Key: AI/AN = American Indian or Alaska Native; API = Asian or Pacific Islander.
Source: Centers for Medicare & Medicaid Services, Minimum Data Set, 2000-2009. Data for long-stay residents are from the third quarter of each calendar year. Data for short-stay residents are full calendar-year estimates.
Denominator: Short-stay and high-risk long-stay nursing home residents in Medicare- or Medicaid-certified nursing and long-term care facilities.
Note: For this measure, lower rates are better. White, Black, API, and AI/AN are non-Hispanic groups; Hispanic includes all races.

  • From 2000 to 2009, the rate of short-stay residents with pressure sores fell (data not shown).xxxvi For high-risk long-stay residents, the rate also fell (data not shown).xxxvii Decreases included all racial/ethnic groups (Figure 2.56).
  • In all years and for both short-stay and high-risk long-stay residents, Blacks and Hispanics were more likely than Whites to have pressure sores.
  • The 2008 top 5 State achievable benchmark for short-stay residents was 12%.xxxviii At the current 2% annual rate of decrease, this benchmark could be attained overall in about 12 years. Whites and Blacks could attain the benchmark in about 11 years. APIs, AI/ANs, and Hispanics would take between 13 and 25 years to attain this benchmark.
  • The 2008 top 5 State achievable benchmark for high-risk long-stay residents was 7%.xxxix At the current 2% annual rate of decrease, this benchmark could be attained overall in about 12 years. Whites could achieve the benchmark in about 9 years. Blacks, APIs, AI/ANs, and Hispanics would take between 15 and 19 years to attain this benchmark.

Also, in the NHQR:

  • From 2000 to 2009, the rate of short-stay residents with pressure sores fell. The rate also fell for high-risk long-stay residents. Improvements included lower rates for both males and females.
  • Short-stay residents have higher rates of pressure sores than high-risk long-stay residents. Some of these patients may be admitted to nursing homes because of or with sores acquired during an acute care hospitalization.
  • In all years, males were more likely than females to have pressure sores.
Help With Emotional and Spiritual Needs

Hospice care is generally delivered at the end of life to patients with a terminal illness or condition who desire palliative medical care; it also includes practical, psychosocial, and spiritual support for the patient and family. The goal of end-of-life care is to achieve a "good death," defined by the IOM as one that is "free from avoidable distress and suffering for patients, families, and caregivers; in general accord with the patients' and families' wishes; and reasonably consistent with clinical, cultural, and ethical standards" (Field & Cassell, 1997).

The National Hospice and Palliative Care Organization's Family Evaluation of Hospice Care survey examines the quality of hospice care for dying patients and their family members. Family respondents report how well hospices respect patients' wishes, communicate about illness, control symptoms, support dying on one's own terms, and provide family emotional support.xl

Management: Right Amount of Emotional Support Among Hospice Patients

Dying is stressful. Patients at the end of life may develop depression or anxiety disorders. Health care systems and providers need to be attuned to recognizing and responding to the emotional and spiritual needs of patients with life-limiting illness and their families.

 

Figure 2.57. Hospice patients age 18 and over who did NOT receive the right amount of help for feelings of anxiety or sadness, by race and ethnicity, 2008-2010

Figure 2.57. Hospice patients age 18 and over who did NOT receive the right amount of help for feelings of anxiety or sadness, by race and ethnicity, 2008-2010. For details, go to [D] Text Description below.

Figure 2.57. Hospice patients age 18 and over who did NOT receive the right amount of help for feelings of anxiety or sadness, by race and ethnicity, 2008-2010. For details, go to [D] Text Description below.

[D] Select for Text Description.

Key: AI/AN = American Indian or Alaska Native; API = Asian or Pacific Islander.
Source: National Hospice and Palliative Care Organization, Family Evaluation of Hospice Care, 2008-2010.
Denominator: Adult hospice patients.
Note: For this measure, lower rates are better.

  • In all years, Blacks, APIs, and AI/ANs were less likely than Whites and Hispanics were less likely than non-Hispanic Whites to receive the right amount of emotional support (Figure 2.57).
  • The 2009 top 5 State achievable benchmark was 6%.xli Data are insufficient to assess progress toward this goal.

Also, in the NHQR:

  • The percentage of hospice patients whose families reported that they did not receive the right amount of help for feelings of anxiety or sadness was 10% in 2010.
  • Between 2008 and 2010, hospice patients ages 18-44 and 45-64 were less likely than patients age 65 and over to receive the right amount of emotional support.
Effective Communication
Management: Enough Information About What To Expect Among Hospice Family Caregivers

Patients at the end of life and their families need clear information about treatment options, prognosis, and advance directives, and what to expect while the patient is dying. Health care providers need to be skilled at eliciting patient's values and preferences, accepting of different cultural and religious choices, and committed to continuing care regardless of patient treatment decisions.

 

Figure 2.58. Hospice patients age 18 and over whose family caregivers wanted more information about what to expect while the patient was dying, by race and ethnicity, 2008-2010

Figure 2.58. Hospice patients age 18 and over whose family caregivers wanted more information about what to expect while the patient was dying, by race and ethnicity, 2008-2010. For details, go to [D] Text Description below.

Figure 2.58. Hospice patients age 18 and over whose family caregivers wanted more information about what to expect while the patient was dying, by race and ethnicity, 2008-2010. For details, go to [D] Text Description below.

[D] Select for Text Description.

Key: AI/AN = American Indian or Alaska Native; API = Asian or Pacific Islander.
Source: National Hospice and Palliative Care Organization, Family Evaluation of Hospice Care, 2008-2010.
Denominator: Adult hospice patients.
Note: For this measure, lower rates are better.

  • In all years, family caregivers of API and AI/AN hospice patients were more likely than family caregivers of White patients to want more information about what to expect while the patient was dying (Figure 2.58). Family caregivers of Hispanic hospice patients were more likely than family caregivers of non-Hispanic White patients to want more information.
  • The 2009 top 5 State achievable benchmark was 12%.xlii Data are insufficient to assess progress toward this goal.

Also, in the NHQR:

  • The percentage of hospice patient family caregivers who reported that they wanted more information about what to expect while the patient was dying was 15% in 2010.
  • Between 2008 and 2010, family caregivers of hospice patients ages 18-44 and 45-64 were more likely than family caregivers of patients age 65 and over to want more information about dying.
High-Quality Palliative Care
Management: Care Consistent With Patient's Wishes Among Hospice Patients

Hospice care should respect patients' stated goals for care. This includes shared communication and decisionmaking between providers and hospice patients and their family members and respect for cultural and religious beliefs.

 

Figure 2.59. Hospice patients age 18 and over who did NOT receive care consistent with their stated end-of-life wishes, by race and ethnicity, 2008-2010

Figure 2.59. Hospice patients age 18 and over who did NOT receive care consistent with their stated end-of-life wishes, by race and ethnicity, 2008-2010. For details, go to [D] Text Description below.

Figure 2.5. Age-adjusted breast cancer deaths per 100,000 women, by race and ethnicity, 2000-2007. For details, go to [D] Text Description below.

[D] Select for Text Description.

Key: AI/AN = American Indian or Alaska Native; API = Asian or Pacific Islander.
Source: National Hospice and Palliative Care Organization, Family Evaluation of Hospice Care, 2008-2010.
Denominator: Adult hospice patients.
Note: For this measure, lower rates are better.

  • In all years, Blacks, APIs, and AI/ANs were less likely than Whites and Hispanics were less likely than non-Hispanic Whites to receive end-of-life care consistent with their wishes (Figure 2.59).
  • The 2009 top 5 State achievable benchmark was 4%.xliii Data are insufficient to assess progress toward this goal.

Also, in the NHQR:

  • The percentage of hospice patients whose families reported that they did not receive end-of-life care consistent with their stated wishes was 6% in 2010.

xxviii. ADLs consist of basic self-care tasks, such as bathing, dressing, eating, transferring, using the toilet, and walking.
xxix. IADLs consist of tasks needed for a person to live independently, such as shopping, doing housework, preparing meals, taking medications, using the telephone, and managing money.
xxx. The top 5 States contributing to the 2008 achievable benchmark are District of Columbia, Hawaii, Kansas, South Carolina, and Utah.
xxxi. In Olmstead v. L.C., 527 U.S. 581 (1999), the U.S. Supreme Court concluded that the unjustified institutionalization of people with disabilities is a form of unlawful discrimination under the Americans With Disabilities Act of 1990, 42 U.S.C. 12101 et seq. The Court held that States are required to provide community-based services for people with disabilities who would otherwise be entitled to institutional services when: (1) such placement is appropriate; (2) the affected person does not oppose such treatment; and (3) the placement can be reasonably accommodated, taking into account the resources available to the State and the needs of other individuals with disabilities. More information about the HHS Office for Civil Rights' Olmstead enforcement efforts is available at http://www.hhs.gov/ocr/civilrights/understanding/disability/serviceolmstead/index.html.
xxxii. The top 5 States that contributed to the 2008 achievable benchmark are Alabama, Alaska, New Jersey, Oklahoma, and Oregon.
xxxiii. Medicare FFS patients represent only a portion of all home health patients.
xxxiv. Cost estimates for nursing home and home health services include only costs for freestanding skilled nursing facilities, nursing homes, and home health agencies and not those that are hospital based.
xxxv. The top 5 States contributing to the 2008 achievable benchmark are Georgia, Hawaii, New Jersey, Rhode Island, and South Carolina.
xxxvi. Short-stay residents stay fewer than 30 days in a nursing home, typically following an acute care hospitalization.
xxxvii. Long-stay residents enter a nursing facility typically because they are no longer able to care for themselves at home; they tend to remain in the facility for several months or years. High-risk residents are those who are in a coma, do not get the nutrients needed to maintain skin health, or cannot change position on their own.
xxxviii. The top 5 States that contributed to the achievable benchmark are Colorado, Iowa, Minnesota, Nebraska, and Utah.
xxxix. The top 5 States that contributed to the achievable benchmark are Hawaii, Minnesota, Nebraska, New Hampshire, and North Dakota.
xl. This survey provides unique insight into end-of-life care and captures information about a large percentage of hospice patients but is limited by nonrandom data collection and a response rate of about 40%. Survey questions were answered by family members, who might not be fully aware of the patients' wishes and concerns. These limitations should be considered when interpreting these findings.
xli. The top 5 States contributing to the achievable benchmark are Alabama, Alaska, Arkansas, Kansas, and South Carolina.
xlii. The top 5 States contributing to the achievable benchmark are Iowa, Kansas, Kentucky, Nebraska, and West Virginia.
xliii. The top 5 States contributing to the achievable benchmark are Arkansas, Illinois, Minnesota, Montana, and Virginia.



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Page last reviewed April 2012
Internet Citation: Chapter 2. Effectiveness of Care (continued, 4): National Healthcare Disparities Report, 2011. April 2012. Agency for Healthcare Research and Quality, Rockville, MD. http://www.ahrq.gov/research/findings/nhqrdr/nhdr11/chap2d.html