 |
|
Urban-Rural Differences in the Quality of Care for Medicare Patients With Acute Myocardial Infarction
Kazim Sheikh, MD;
Claudia Bullock
Arch Intern Med. 2001;161:737-743.
ABSTRACT
| |
Background There are urban-rural differences in health care utilization in Kansas.
This study was conducted to determine if similar differences exist in the
quality of inpatient care provided for patients with acute myocardial infarction
(AMI).
Methods All acute care hospitals in the state were stratified into 12 urban,
31 semirural, and 76 rural hospitals according to their location. Data from
medical records of 2521 Medicare patients 65 years and older who had survived
AMI and were discharged alive from hospitals during an 8-month period in 1994/1995
were abstracted. The measures of the quality of care (quality indicators [QIs])
were the use of aspirin (during hospital stay and at discharge) and the administration
of ß-blockers, intravenous (IV) nitroglycerin, heparin, and reperfusion
by thrombolytic therapy or primary angioplasty.
Results A significantly higher proportion of ideal candidates for the use of
aspirin during hospital stay and at discharge, heparin, and IV nitroglycerin
received these medications in urban hospitals, and a lower proportion of similar
patients received these medications in rural hospitals compared with the patients
in semirural hospitals (P<.001). Similar trends
in each of the 6 QIs were observed for less than ideal patients (P<.05). Patient age was associated with a relatively poor quality
of care in terms of the 6 QIs. Except for the administration of IV nitroglycerine
to less than ideal patients, age adjustments did not change the observed urban-rural
differences in the QI measures.
Conclusion Relatively poor quality of care for patients with AMI was provided by
rural hospitals where greater opportunity for improvement exists.
INTRODUCTION
REGIONAL, interstate, and intrastate variations in the health insurance
coverage and utilization by the elderly population are well known to the Health
Care Financing Administration (HCFA) and the health care industry. The HCFA's
administrative data have also shown that marked differences exist between
urban and rural areas of the country with respect to the distributions of
health care providers and utilization.1 Inappropriate
or greater utilization of health care is known to be associated with lower
socioeconomic status of patients2-3
and residency in rural areas.4
In a previous study,5 Medicare beneficiaries
residing in the rural counties of the state of Kansas seemed to have had equal
access to primary care providers, but their utilization of health care was
greater than that of the beneficiary populations in the urban counties possibly
due to untimely, inadequate, unnecessary, and/or substandard health care provided
to the residents of rural counties. This article describes the results of
a study of Medicare beneficiaries that explored the possibility that the quality
of health care in the rural areas of Kansas was poorer than that in the urban
areas. Preexisting data on inpatient care for acute myocardial infarction
(AMI) were used for this descriptive study. This topic was chosen because
direct, specific measures of the quality of care for AMI based on the clinical
guidelines and reliable clinical data were available for the study.
METHODS
Health care data collected for HCFA's Cooperative Cardiovascular Project
(CCP)6 were available for this study, hence
the topic of AMI. The CCP was the first national project in HCFA's Health
Care Quality Improvement Program.7 This program
was initiated in 1992 with the objectives of reducing variation among providers
and improving the quality of care in selected clinical areas provided to Medicare
beneficiaries.8 After a pilot run in 1993,
CCP was implemented nationwide in 1995. The indicators of good quality inpatient
care of patients with AMI were developed by a panel of experts convened by
HCFA and the American Medical Association. They were based on the American
College of Cardiology (ACC) and American Heart Association's (AHA) clinical
guidelines.9 Good quality of care was, therefore,
defined as good clinical practice measured by compliance with the ACC/AHA
guidelines. The data collection tools and data analysis programs developed
for the pilot project and used for the nationwide project have been previously
described.6, 10-11
Eligibility for a medication or a procedure was defined as a confirmed first
AMI in a patient who was discharged alive. Those eligible patients for whom
the treatment would almost always be indicated (no contraindications) using
ACC/AHA guidelines were regarded as the "ideal" candidates, and the remaining
"less than ideal" patients were those for whom the therapy could be controversial.10 The criteria for administering therapy in the 2 groups
of patients were identical: both groups should have received similar, appropriate
therapy. These criteria and definitions (Table 1) were used to develop appropriate algorithms, which were
converted into simple computer programs for data analysis.
|
|
|
|
Table 1. Exclusion Criteria for Quality Indicators of Initial Hospitalization
for Patients With AMI*
|
|
|
A sample of discharge diagnosis-specific inpatient medical records of
acute care hospitals from each state were abstracted in a preset, standard
manner, and the quality of the clinical data and the validity of the quality
indicators (QIs) were assured. Data reliability was assessed by reabstracting
a sample of medical records and examining interabstractor agreements.10 All discrepancies were analyzed, and the data abstraction
process was improved to achieve acceptable data quality. Similarly, the measures
of QIs, eligibility, and ideal candidate status derived from a sample of abstracted
data elements were validated against the reabstracted data on the therapies
administered and were found to be reliable.12-13
The diagnosis of AMI (International Classification of Diseases,
Ninth Edition Revision, Clinical Modification code 410) was confirmed
by documentation in the medical records of either a serum creatine kinase
MB fraction above 5%, a serum lactate dehydrogenase level more than 1.5 times
the upper limit of the normal value and a lactate dehydrogenase isoenzyme
1 level greater than that of lactate dehydrogenase isoenzyme 2, or 2 of the
following 3 criteria: chest pain, a serum creatine kinase level twice that
hospital's normal value, and a new AMI reported in an electrocardiogram report.
The severity of illness was estimated according to the Medicare Mortality
Predictor System (MMPS), which predicts disease-specific 30-day mortality.14 The Acute Physiology and Chronic Health Evaluation
score15 (a disease severity classification)
is one of the variables used in MMPS.
The CCP baseline (preintervention) sampling frame for each state was
all state-specific, fee-for-service hospital bills (UB-92 claims) for inpatient
services provided during a specified period in the Medicare National Claims
History File.6 The 100% sample for Kansas consisted
of 2521 records for Medicare patients discharged alive from nongovernmental
acute care hospitals during an approximate 8-month period in 1995 with a diagnosis
of AMI. The CCP's postintervention data were not available for this study.
The data on 6 major QIs were used in this study of urban-rural differences.
These QIs were (1) administration of aspirin during hospital stay; (2) prescription
of aspirin at hospital discharge; (3) intravenous (IV) administration of nitroglycerin
to patients with persistent chest pain; (4) administration of full- or low-dose
heparin during hospitalization; (5) reperfusion by administration of thrombolytic
therapy or primary angioplasty within 12 hours of arrival at the hospital;
and (6) prescription of ß-blockers at hospital discharge. The inclusion
and exclusion criteria for these QIs are given in Table 1. The main eligibility criterion was that the patients must
have been discharged alive. This restriction was introduced so that there
would be opportunities for administering the therapies of interest during
the hospitalizations, particularly the prescription of ß-blockers at
discharge. Other CCP QIs were not selected for this study because of the small
number of ideal candidates who received these therapies. The analyses were
based on the data for 2285 eligible patients.
The state of Kansas was divided into 3 categories of counties according
to the classification used in the previous study of urban-rural differences
in health care utilization in the state.5 Four
counties with more than 20 000 beneficiaries residing in each were regarded
as the urban counties. Twenty counties, each having 4000 to 20 000 beneficiaries
living in them, were regarded as the semirural counties, and the remaining
81 counties were the rural counties. Accordingly, 38.4%, 30.8%, and 30.8%
of the beneficiaries enrolled in Medicare any time during 1995 resided in
the urban, semirural, and rural counties, respectively. The purpose of using
this classification was to have roughly equal numbers of beneficiaries in
each category for comparisons. This arbitrary classification correlates well
with those based on the general population density. The study sample of medical
records from the participating acute care hospitals in Kansas were assigned
to the 3 county categories according to the location of the hospitals.
The statistical significance of the differences between means, proportions,
and their trends were estimated using the t test,
uncorrected  2 test, and 2 for linear trend,
respectively. The direct standardization method, with the state patient population
as the standard, was used for age adjustments.16
RESULTS
The characteristics of all eligible patients are given in Table 2. The patients in the urban hospitals were younger, and those
in rural hospitals were older than those in semirural hospitals. The average
number of patients with AMI discharged from each of the 12 urban, 31 semirural,
and 76 rural hospitals in Kansas were 106, 18, and 6, respectively. The corresponding
average number of beds in the hospitals were 458, 105, and 39, respectively.
|
|
|
|
Table 2. Characteristics of Patients According to the Locations of
Hospitals in Kansas, 1994-1995 CCP Baseline*
|
|
|
The numbers and percentages of eligible patients and ideal candidates
for the therapy or procedure in each of the 6 QIs are given in Table 3. Variations in the numbers of patients found to be eligible
for each QI and the percentage of eligible patients regarded as the ideal
candidates were to be expected because different eligibility criteria, indications,
and contraindications were used for individual QIs.10
|
|
|
|
Table 3. Patients With AMI Who Were Eligible and Ideal Candidates for
Therapy as Indicated by Clinical Guidelines (Quality Indicators)*
|
|
|
Table 4 gives the number
of ideal and less than ideal candidates for each QI according to the location
of the hospital and percentage of patients in each category who received therapy
or procedures as determined by the QI. Compared with the eligible patients
in semirural and rural hospitals, significantly lower proportions of eligible
patients in the urban hospitals were ideal candidates for heparin and IV nitroglycerine
therapy (P<.05). In the case of ß-blocker
therapy, the trend was in the opposite direction. Aspirin was administered
during hospital stay to 87.8%, 83.9%, and 75.0% of the ideal candidates in
the urban, semirural, and rural hospitals, respectively; the corresponding
respective percentages for the less than ideal patients were 79.9%, 59.1%,
and 56.0% (Table 4). These trends
are statistically significant (P<.001).
|
|
|
|
Table 4. Percentage of Patients With Confirmed AMI Who Received Therapy
or Procedure in Hospitals in Kansas, 1994-1995 CCP Baseline*
|
|
|
Heparin was more frequently administered to the ideal candidates in
urban hospitals and less frequently to the ideal candidates in rural hospitals
than it was in semirural hospitals (P<.001). Similarly,
a significantly higher proportion of less than ideal patients in the urban
hospitals received heparin compared with patients in nonurban hospitals (P<.001), but there was no significant difference between
the semirural and rural hospitals (Table
4).
Intravenous nitroglycerin was ideally indicated for 596 patients with
persistent chest pain during hospitalization (Table 4). In the case of both ideal and less than ideal candidates,
IV nitroglycerin was administered more often to patients in the urban hospitals
and less often to patients in rural hospitals than it was in semirural hospitals
(P<.03).
Reperfusion (thrombolytic therapy or primary angioplasty) was performed
on 83.3% of those ideal candidates who had been hospitalized in the urban
hospitals compared with 72.3% of patients in semirural hospitals and 67.9%
of patients in rural hospitals. However, these differences were statistically
insignificant. The percentage of less than ideal candidates who received reperfusion
was highest (24.6%) in the urban hospitals and lowest (11.6%) in the rural
hospitals (Table 4). Similarly,
the percentages of the combination of ideal and less than ideal patients who
received reperfusion therapy were 28.9%, 22.8%, and 15.8% in the urban, semirural,
and rural hospitals, respectively. These trends are statistically significant
(P<.001).
Table 4 shows that for both
the ideal and less than ideal candidates, a higher proportion of patients
in the urban hospitals and a lower proportion of patients in rural hospitals
were prescribed aspirin at discharge than the proportion of patients in semirural
hospitals (P<.001). ß-Blockers were prescribed
at discharge to 31.3%, 25.0%, and 22.5% of less than ideal candidates who
had been hospitalized in the urban, semirural, and rural hospitals, respectively
(Table 4), a statistically significant
trend (P<.05). However, the numbers of ideal candidates
who had been hospitalized in nonurban hospitals were too small for meaningful
comparisons.
Figure 1 shows that the age
of the patient was inversely correlated with the likelihood of the ideal candidates
receiving aspirin during hospital stay and at discharge, IV nitroglycerin,
and heparin. There was no evidence for this effect of age being restricted
to only rural hospitals. Age adjustments to the proportions of patients who
received the therapy or procedure did not change the trends in the observed
urban-rural differences (Table 4).
However, the trend in the urban-rural differences in the proportions of less
than ideal patients who received IV nitroglycerin was not statistically significant
after age adjustment (Table 4).
|
|
|
|
Relationship between age and the percentage of ideal candidates who
received therapy or procedure. a Indicates aspirin during hospital stay; b,
aspirin at discharge; c, intravenous nitroglycerin; d, heparin; e, reperfusion;
and f, ß-blockers at discharge. Statistically significant linear trends
for all but reperfusion and ß-blockers at discharge, P<.01.
|
|
|
COMMENT
Regional variation in the clinical management of AMI in terms of the
ACC and AHA guidelines within the United States is well known.6, 17-18
Considerable variation in the rate of coronary angioplasty procedures performed
on Medicare patients was also found among 13 large areas in the United States.
However, medically necessary procedures could not be distinguished from unnecessary
procedures.19 Although coronary angiography
for clinically similar groups of Medicare patients with AMI was performed
more often in Texas than in New York State, the 2-year postdischarge mortality
rate was greater and angina reported by the patients was more frequent in
Texas than in New York.20
The results of this study suggest that in 1994/1995, the quality of
inpatient care for AMI, in terms of 6 major QIs, provided to Medicare beneficiaries
by acute care hospitals in Kansas was inferior in rural areas compared with
the hospitals in the urban areas. It may be that the greater utilization of
health care by rural beneficiaries relative to the beneficiaries residing
in the urban areas of Kansas seen in our previous study5
may be partly explained by the relatively poor quality of care provided by
rural hospitals. This hypothesis is supported by evidence from other studies
of Medicare patients that show relatively poor quality of inpatient care for
AMI, congestive heart failure, pneumonia, stroke, hip fracture, and chronic
atrial fibrillation provided by small rural hospitals compared with larger
urban hospitals.21-22 Care for
diabetes has also been found to be relatively inferior in the rural areas
of Alabama, Iowa, and Maryland.23
As expected, the AMI case volume of urban hospitals in Kansas far exceeded
that of semirural and rural hospitals, and it may be that these small rural
hospitals were also not as well equipped with cardiology services. The relationship
between hospital case volume and outcome is well known.24
A recent analysis of data on a national CCP sample has also confirmed an association
of higher AMI case volume and rural location of the hospitals with increased
risk of death.25 Another independent analysis
of the same data set showed that a higher percentage of Medicare patients
hospitalized for AMI who were ideal candidates for aspirin and ß-blockers
received these medications in "top-ranked cardiology hospitals" and a lower
percentage of similar patients received these medications in hospitals not
equipped for cardiac catheterization, coronary angioplasty, and coronary bypass
surgery than patients in hospitals that were equipped for these procedures
but were not in the top rank.11 Almost all
of the top-ranked hospitals were located in urban areas of the country, and
most of the nonequipped hospitals were small community and rural hospitals.11 Consequently, the results of our study in Kansas
are consistent with those of these 2 studies,11, 25
which suggests that the urban-rural disparity observed in our study is not
limited to Kansas.
The data used in these studies excluded data on Medicare beneficiaries
enrolled in the managed care sector, mainly in the urban areas of the country.
Consequently, comparisons between the fee-for-service and managed care sectors
were not possible. Since the collection of CCP data, the quality of care for
elderly patients with AMI has improved to some extent.6, 26
Future studies should use recent data, examine time trends and patterns of
care after discharge, and identify modifiable characteristics or practices
of health care providers, all of which could be used to develop effective
interventions and achieve further improvement in the quality of care. It would
be useful to study similar variance in adherence to the clinical guidelines
for AMI care in patient populations younger than 65 years and to compare the
quality of care provided in the inner cities with that provided in affluent
and suburban neighborhoods in urban areas.
The reliability of the data used in this study was partly dependent
on the reliability of documentation in the hospital medical records. It may
be that documentation in medical records of urban hospitals in Kansas was
more accurate and complete than that in the rural hospitals. Although data
were abstracted from all medical records in a standard manner by the same
group of abstractors and efforts were made to control the quality of data
abstraction process, there may have been errors in interpretation, which may
have distorted the evidence for the administration of therapies. However,
owing to the randomness of such errors, there was no reason to suspect bias.
The algorithms for the QIs, eligibility criteria, and contraindications
were developed on the basis of the clinical guidelines. Adjustments for hospital
and patient characteristics, the severity of illness, case mix, etc, were
considered unnecessary because the same set of variables, criteria, and algorithms
were used in determining adherence to the guidelines in each group of hospitals.
Consequently, patients in the 3 groups of hospitals were similar with respect
to their eligibility for therapy. Similar eligibility criteria were used for
the ideal and less than ideal patients, and there were no differences between
the 2 groups with respect to the appropriateness of therapy. The measures
of QIs were adjusted for age because age seemed to be a confounding variable.
However, these adjustments did not materially change the urban-rural differences.
Although the prevalence of comorbidities and the adverse effects of certain
drugs are associated with age, the age of the patient should not by itself
influence the protocol for managing AMI.27
The QIs based on ACC/AHA guidelines account for all contraindications and
eligibility criteria, and these guidelines do not discriminate on the basis
of age.9 Those clinical trials that included
older patients with AMI do not support the restriction against treating these
patients with ß-blockers and thrombolytic agents.24, 27
Although the risks from these drugs are greater in older patients, the opportunities
for reducing the risk of AMI-related complications and death are also greater
because the risk of these adverse outcomes is also age-related.
In this study, aggregate frequencies of the use of medications and procedures
for ideal candidates in one group of hospitals were compared with those for
similar patients in other groups. It may be that severely ill patients or
those with serious comorbidities from rural areas of Kansas were transferred
from rural hospitals to hospitals in the urban areas. If this was the case,
it would not have altered the observed differences between the 2 groups of
hospitals because the same standard criteria for eligibility for the therapies
were used across the state. Accordingly, if there were more sicker patients
in the urban hospitals, those with contraindications due to their comorbidities
would not have been eligible, and they would have been excluded. Furthermore,
if a therapy was withheld in urban hospitals because the patients were too
sick, it would have resulted in underestimation, not exaggeration, of the
urban-rural differences. Consequently, differential severity of illness could
not have biased the results of this study.
This preliminary study used preexisting CCP data available to the investigators.
These data included the actual, specific, and direct measures of the quality
of care for patients with AMI that were based on the accepted clinical guidelines.
Consequently, there was no need for using inferior, nonspecific, indirect
QIs such as mortality, complications, or readmissions to study the urban-rural
differences. The inverse relationship between the quality of care for patients
with AMI and postdischarge mortality has been established in several clinical
trials28-30 and
previous studies of CCP data.6, 10-11,25, 31
Replication of their findings was considered unnecessary. It is recognized
that if reliable process measures are available, there are substantiated benefits
to using these measures instead of measuring outcomes.32
CCP and other data clearly show that aspirin, ß-blocker, and thrombolytic
therapy reduce post-AMI mortality by as much as 25% in Medicare patients and
in younger patients.6, 10-11,25, 30-31
Yet, approximately a third of elderly Medicare patients with AMI who had no
contraindications to aspirin did not receive it within the first 2 days of
hospitalization,31 half of the ideal candidates
were not prescribed ß-blockers at discharge,6
and 24% of the ideal candidates for thrombolytic therapy did not receive it.26 Even the urban hospitals in this study and the top-ranked
hospitals in the national CCP sample11 failed
to prescribe aspirin and ß-blockers at discharge to 4% to 18% and 25%
to 63% of the ideal candidates, respectively. Failure to adhere to the clinical
guidelines was much more severe in small rural hospitals.
The length of stay in rural hospitals was much shorter than that in
urban hospitals. Since the length of stay was not an indication or contraindication
for the therapies of interest, it could not have confounded the urban-rural
differences in the quality of care. The prevalence of left ventricular ejection
fraction (LVEF) below 41% among the patients in the rural hospitals was also
much lower than that in the urban hospitals. Left ventricular ejection fraction
was associated with the eligibility for only 1 QI (prescription of ß-blockers
at discharge). However, the urban-rural differences with respect to other
QIs could not have been affected by the differences in LVEF. There were fewer
cardiologists in rural counties than in urban areas of Kansas.5
It may be that hospitals with attending cardiologists provided better care
for patients with AMI. However, another recent study of the CCP data for California
suggested that the differences in the use of recommended therapies by physician
speciality are generally small and do not explain the differences in patient
outcome.33
Some of the patients with AMI were deprived of reperfusion therapy because
of the delay in presentation.26 Such delays
would be expected to be more frequent in rural areas. Even though thrombolytic
therapy is increasingly used in AMI cases, physicians are reluctant to administer
thrombolytic agents because of the risk of cerebral hemorrhage, particularly
in elderly patients.26 It is understandable
that the decision to prescribe a simple drug like aspirin to elderly patients
is complicated by frequent comorbidities and drug interactions,10
but why are such decisions more difficult to make in rural hospitals? It has
been suggested that nonclinical factors may be responsible for variation in
the use of aspirin and ß-blockers in the management of AMI.6
Relatively poor quality of health care in rural areas has also been attributed
to poor access to health care, poor access to medical education, delays in
initiating critical therapy, and to rural hospitals being accustomed to providing
"charity" care.34 Furthermore, a relatively
higher proportion of rural beneficiaries in Kansas were dually eligible (eligible
for both Medicaid and Medicare),5 and compared
with those beneficiaries eligible for only Medicare, the dually eligible beneficiaries
have been known to receive relatively inferior health care35
and have a higher risk of death.36 Our study
and several other studies suggest that there are greater opportunities for
improving the delivery of care in more than 1 clinical area in the rural districts
than there are in metropolitan regions.
AUTHOR INFORMATION
Accepted for publication September 21, 2000.
Presented at the annual meeting of the American Public Health Association,
Boston, Mass, November 2000.
The authors acknowledge the assistance of Thomas A. Marciniak, MD, of
the Health Care Financing Administration in accessing and interpreting the
CCP data.
The views expressed in this article do not represent the views or policies
of the Health Care Financing Administration or the US government.
Corresponding author: Kazim Sheikh, MD, Health Care Financing Administration,
601 E 12th St, Room 227, Kansas City, MO 64106 (e-mail: KSheikh{at}HCFA.Gov)
From the Health Care Financing Administration, Kansas City, Mo (Dr
Sheikh and Ms Bullock).
REFERENCES
| |
1. Health Care Financing Administration. Health Care Financing Review: Medicare and Medicaid
Statistical Supplement, 1996. Baltimore, Md: US Dept of Health and Human Services; 1996. Publication
03386.
2. Gornick ME, Eggers PW, Reilly TW, et al. Effects of race and income on mortality and use of services among Medicare
beneficiaries. N Engl J Med. 1996;335:791-799.
FREE FULL TEXT
3. Merrel K, Colby DC, Hogan C. Medicare beneficiaries covered by Medicaid buy-in agreements. Health Aff (Millwood). 1997;16:175-184.
ABSTRACT
4. Blazer DG, Landerman LR, Fillenbaum G, Horner R. Health services access and use among older adults in North Carolina
urban vs rural residents. Am J Public Health. 1995;85:1384-1390.
FREE FULL TEXT
5. Sheikh K, Bullock C. Urban-rural differences in Medicare in Kansas. Kans Med. 1998;98:56-61.
6. Krumholz HM, Radford MJ, Wang Y, Chen J, Heiat A, Marciniak TA. National use and effectiveness of ß-blockers for the treatment
of elderly patients after acute myocardial infarction: National Cooperative
Cardiovascular Project. JAMA. 1998;280:623-629.
FREE FULL TEXT
7. Jencks SF, Wilensky GR. The health care quality improvement initiative: a new approach to quality
assurance in Medicare. JAMA. 1992;268:900-903.
FULL TEXT
|
ISI
| PUBMED
8. Sheikh K. Defining and achieving quality of medical care. Am J Med Qual. 1998;13:59-62.
FREE FULL TEXT
9. American College of Cardiology, American Heart Association. Guidelines for the management of patients with acute myocardial infarction:
executive summary. Circulation. 1996;94:2341-2350.
FREE FULL TEXT
10. Ellerbeck EF, Jencks SF, Radford MJ, et al. Quality of care for Medicare patients with acute myocardial infarction. JAMA. 1995;273:1509-1514.
ABSTRACT
11. Chen J, Radford MJ, Wang Y, Marciniak TA, Krumholz HM. Do "America's best hospitals" perform better for acute myocardial infarction? N Engl J Med. 1999;340:286-292.
FREE FULL TEXT
12. Lambert-Huber DA, Ellerbeck EF, Wallace RG, Radford MJ, Kresowik TF, Allison JA. Quality of care indicators for patients with acute myocardial infarction:
pilot validation of the indicators. Clin Perform Qual Health Care. 1994;2:219-222.
13. Huff ED. Comprehensive reliability assessment and comparison of quality indicators
and their components. J Clin Epidemiol. 1997;50:1395-1404.
FULL TEXT
|
ISI
| PUBMED
14. Daley J, Jencks SF, Draper D, Lenhart G, Thomas N, Walker J. Predicting hospital-associated mortality for Medicare patients: a method
for patients with stroke, pneumonia, acute myocardial infarction, and congestive
heart failure. JAMA. 1988;260:3617-3624.
ABSTRACT
15. Knaus WA, Draper EA, Wagner DP, Zimmerman JE. APACHE II: a severity of disease classification system. Crit Care Med. 1985;13:818-829.
ISI
| PUBMED
16. Rothman K. Standardization of rates. In: Modern Epidemiology. Boston, Mass: Little
Brown & Co Inc; 1986:41-49.
17. Pilote L, Califf RM, Sapp S, et al. Regional variation across the United States in the management of acute
myocardial infarction. N Engl J Med. 1995;333:565-572.
FREE FULL TEXT
18. O'Connor GT, Quinton HB, Traven ND, et al. Geographic variation in the treatment of acute myocardial infarction:
the Cooperative Cardiovascular Project. JAMA. 1999;281:627-633.
FREE FULL TEXT
19. Chassin MR, Brook RH, Park RE, et al. Variation in the use of medical and surgical services by the Medicare
population. N Engl J Med. 1986;314:285-290.
ABSTRACT
20. Guadagnoli E, Hauptman PJ, Ayanian JZ, et al. Variation in the use of cardiac procedures after acute myocardial infarction. N Engl J Med. 1995;333:573-578.
FREE FULL TEXT
21. Keeler EB, Rubenstein LV, Kahn KL, et al. Hospital characteristics and quality of care. JAMA. 1992;268:1709-1714.
ABSTRACT
22. Flaker GC, McGowan DJ, Boechler M, Fortune G, Gage B. Underutilization of antithrombotic therapy in elderly rural patients
with atrial fibrillation. Am Heart J. 1999;137:307-312.
FULL TEXT
|
ISI
| PUBMED
23. Weiner JP, Parente ST, Garnick DW, Fowles J, Lawthers AG, Palmer H. Variation in office-based quality: a claim-based profile of care provided
to Medicare patients with diabetes. JAMA. 1995;273:1503-1508.
ABSTRACT
24. Hannan EL. The relation between volume and outcome in health care. N Engl J Med. 1999;340:1677-1679.
FREE FULL TEXT
25. Thiemann DR, Coresh J, Oetgen WJ, Powe NR. The association between hospital volume and survival after acute myocardial
infarction in elderly patients. N Engl J Med. 1999;340:1640-1648.
FREE FULL TEXT
26. Gurwitz JH, Goldberg RJ. Coronary thrombolysis for the elderly: is clinical practice really
lagging behind evidence of benefit? JAMA. 1997;277:1723-1724.
FULL TEXT
|
ISI
| PUBMED
27. Gollub SB. Is intensive drug therapy appropriate for older patients? Lancet. 1999;353:940-941.
FULL TEXT
|
ISI
| PUBMED
28. Yusuf S, Peto R, Lewis J, Collins R, Sleight P. Beta blockade during and after myocardial infarction: an overview of
the randomized trials. Prog Cardiovasc Dis. 1985;27:335-371.
ISI
| PUBMED
29. The ISIS-2 (Second International Study of Infarct Survival) Collaborative
Group. Randomised trial of intravenous streptokinase, oral aspirin, both,
or neither among 17,187 cases of suspected acute myocardial infarction:
ISIS-2. ISIS-2 (Second International Study of Infarct Survival) Collaborative Group. Lancet. 1988;2:349-360.
PUBMED
30. Lau J, Antman EM, Jimenez-Silva J, et al. Cumulative meta-analysis of therapeutic trials for myocardial infarction. N Engl J Med. 1992;327:248-254.
ABSTRACT
31. Krumholz HM, Radford MJ, Ellerebeck EF, et al. Aspirin in the treatment of acute myocardial infarction in elderly
Medicare beneficiaries: patterns of use and outcomes. Circulation. 1995;92:2841-2847.
FREE FULL TEXT
32. US Congress, Office of Technology Assessment. Identifying Health Technologies That Work: Searching
for Evidence. Washington, DC: US Government Printing Office; 1994. Publication
OTA-H-608.
33. Frances CD, Go AS, Dauterman KW, et al. Outcome following acute myocardial infarction. Arch Intern Med. 1999;159:1429-1436.
FREE FULL TEXT
34. Pearson TA, Lewis C. Rural epidemiology: insights from a rural population laboratory. Am J Epidemiol. 1998;148:949-957.
FREE FULL TEXT
35. Parker J, Gebretsadik T, Sabogal F, Newman J, Lawson HW. Mammography screening among California Medicare beneficiaries: 1993-1994. Am J Prev Med. 1998;15:198-205.
FULL TEXT
|
ISI
| PUBMED
36. McMillan A, Pine PL, Gornick M, Prihoda R. A study of the "crossover population": aged persons entitled to both
Medicare and Medicaid. Health Care Financ Rev. 1983;4:19-46.
PUBMED
RELATED LETTER
Urban-Rural Differences in the Quality of Care for Medicare Patients With Acute Myocardial Infarction
Aldo Mariotto and Kazim Sheikh
Arch Intern Med. 2001;161(19):2386-2387.
EXTRACT
| FULL TEXT
RELATED ARTICLE
Archives of Internal Medicine Reader's Choice: Continuing Medical Education
Arch Intern Med. 2001;161(5):779-780.
FULL TEXT
THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES
|
A Hospital-Randomized Controlled Trial of an Educational Quality Improvement Intervention in Rural and Small Community Hospitals in Texas Following Implementation of Information Technology
Filardo et al.
American Journal of Medical Quality 2007;22:418-427.
ABSTRACT
A comparison of quality of care indicators in urban acute care hospitals and rural critical access hospitals in the United States
Lutfiyya et al.
Int J Qual Health Care 2007;19:141-149.
ABSTRACT
| FULL TEXT
Myocardial Infarction Mortality in Rural and Urban Hospitals: Rethinking Measures of Quality of Care
James et al.
Ann Fam Med 2007;5:105-111.
ABSTRACT
| FULL TEXT
ST-Segment Elevation Myocardial Infarction: Recommendations on Triage of Patients to Heart Attack Centers: Is it Time for a National Policy for the Treatment of ST-Segment Elevation Myocardial Infarction?
Henry et al.
J Am Coll Cardiol 2006;47:1339-1345.
ABSTRACT
| FULL TEXT
Effect of Cuts in Medicare Reimbursement on Process and Outcome of Care for Acute Myocardial Infarction Patients
Volpp et al.
Circulation 2005;112:2268-2275.
ABSTRACT
| FULL TEXT
Pursuing integration of performance measures into electronic medical records: beta-adrenergic receptor antagonist medications
Weiner et al.
Qual Saf Health Care 2005;14:99-106.
ABSTRACT
| FULL TEXT
Equivalent Lengths of Stay of Pediatric Patients Hospitalized in Rural and Nonrural Hospitals
Lorch et al.
Pediatrics 2004;114:e400-e408.
ABSTRACT
| FULL TEXT
Discharge rates for suspected acute coronary syndromes: Is morbidity or empowerment increas |
