CONTRIBUTION
Geographic Variation in the Treatment
of Acute Myocardial Infarction
The Cooperative Cardiovascular Project
Gerald T. O’Connor, PhD, DSc Hebe B. Quinton, MS Neal D. Traven, PhD Lawrence D. Ramunno, MD, MPH T. Andrew Dodds, MD, MPH Thomas A. Marciniak, MD John E. Wennberg, MD, MPHE
ACH YEAR APPROXIMATELY1.5MIL -lion people in the United States experience acute myocardial in-farction (AMI), and approxi-mately one third of these patients die in the acute phase of the AMI. The annual economic burden of AMI is in excess of $60 billion.1Due to its frequency and se-verity, AMI has been the topic of intense scientific and clinical interest. Random-ized trials have confirmed the efficacy of some therapies resulting in evidence-based treatment guidelines.2,3These guide-lines make it possible to evaluate the pro-cesses of care in a meaningful manner and to identify areas for the improvement of the care of patients with AMI.Since 1992 the Health Care Financ-ing Administration has implemented a continuous quality improvement ap-proach to ensuring the quality of care for its Medicare beneficiaries through its Health Care Quality Improvement Ini-tiative.4The first national project of this program is the Cooperative Cardiovas-cular Project (CCP), focusing on the treat-ment of patients with AMI. Quality in-dicators, based on clinical practice guidelines, were developed by a
steer-ing committee.3Data on more than 200 000 patients admitted for treat-ment of AMI were abstracted from clini-cal records. Patients were classified as eli-gible or ideal for the specific therapies described by the quality indicators.
During this same time period, studies were conducted to describe the geographic variation of health care in the United States.5 These studies used Medicare
Author Affiliations: Center for the Evaluative Clini-cal Sciences, Dartmouth MediClini-cal School, Hanover (Drs O’Connor and Wennberg and Ms Quinton), and Northeast Health Care Quality Foundation (Drs Traven, Ramunno, and Dodds), Dover, NH; and Department of Health and Human Services, Health Care Financing Administration, Baltimore, Md (Dr Marciniak).
Corresponding Author and Reprints: Gerald T. O’Connor, PhD, DSc, Center for the Evaluative Clinical Sciences, 330 Strasenburgh Hall, Dartmouth Medical School, Hanover, NH 03755 (e-mail: gerald.t.o’[email protected]).
Context Quality indicators for the treatment of acute myocardial infarction include pharmacologic therapy, reperfusion, and smoking cessation advice, but these thera-pies may not be administered to all patients who could benefit from them.
Objective To assess geographic variation in adherence to quality indicators for treat-ment of acute myocardial infarction.
Design Inception cohort using data from the Health Care Financing Administration Cooperative Cardiovascular Project.
Setting Acute care hospitals in the United States.
Patients A total of 186 800 Medicare beneficiaries hospitalized for treatment of con-firmed acute myocardial infarction from February 1994 through July 1995.
Main Outcome Measures Adherence to quality indicators for pharmacologic therapy, reperfusion, and smoking cessation advice for patients judged to be ideal can-didates for these therapies. The mean rates of adherence to these quality indicators for the entire United States were determined, and the 20th and 80th percentiles of the age- and sex-adjusted rates for each of 306 hospital referral regions were con-trasted (mean rate [20th-80th percentiles]).
Results Aspirin was used frequently both during hospitalization (86.2% [82.6%-90.1%]) and at discharge (77.8% [72.5%-83.9%]). Calcium channel blockers were with-held from most patients with impaired left ventricular function (81.9% [73.6%-90.8%]). Lower rates were seen in the use of angiotensin-converting enzyme inhibitors at dis-charge (59.3% [49.2%-69.2%]); reperfusion, using thrombolytic therapy or coronary angioplasty (67.2% [59.8%-75.1%]); prescription ofb-blockers at discharge (49.5% [35.8%-61.5%]); and for smoking cessation advice (41.9% [32.8%-51.3%]). Conclusions Substantial geographic variation exists in the treatment of patients with acute myocardial infarction, and these gaps between knowledge and practice have important consequences. Therapies with proven benefit for AMI are underused de-spite strong evidence that their use will result in better patient outcomes.
claims data to empirically derive hospi-tal service areas (HSAs), which are local market areas for health care, and hospi-tal referral regions (HRRs). Combining these HRRs with the national sample of data collected by CCP allowed us to study geographic variation in the treatment of AMI in the United States.
METHODS Data Collection
The sampling approach used bills sub-mitted by acute care hospitals (UB-92 claims form data) and contained in the Medicare National Claims History File to identify all Medicare discharges with an
International Classification of Diseases,
Ninth Revision, Clinical Modification
prcipal diagnosis of 410 (myocardial in-farction), excluding fifth digits of 2, which indicate a “subsequent episode of care.”6 Data were collected during 8-month pe-riods, staggered so that all discharge dates were between February 1994 through July 1995. Approximately .003% of the bills submitted could not be linked to medical records. The National Claims History File does not necessarily in-clude bills for all of the approximately 12% of patients treated under Medicare managed care risk contracts. The pri-mary sampling relies on the billing prin-cipal diagnosis of AMI. The accuracy of billing diagnoses has been questioned fre-quently.7,8The criteria for a confirmed AMI required elevated levels of creatine kinase isoenzyme MB or lactate dehy-drogenase with LD1levels greater than LD2levels or 2 of the following: chest pain, 2-fold elevation of the creatine ki-nase level, or electrocardiographic evi-dence of an AMI. This data set contains the 186 800 patients from the 50 states with AMI confirmed by these criteria.
There were also 3 special circum-stances in the sampling scheme. The pi-lot states (Alabama, Connecticut, Iowa, and Wisconsin) were sampled initially between June 1 and December 31, 1992, to test the indicator and abstraction meth-ods and then remeasured between Au-gust 1 and November 30, 1995. Sam-pling in Minnesota was delayed until April through November 1995 so that it would not interfere with a local study of AMI; only about a 60% sample of AMI diagnoses was included in the CCP study. One hospital that initially ignored rec-ord requests was sampled from July 1995 through February 1996. We believe that the sampling strategy used in this study is highly representative of the Medicare fee-for-service patient population in the United States.
Quality Indicators
Quality indicators are measurable as-pects of care that are presumed on the ba-sis of evidence or consensus to be related to the quality of care delivered and to fa-vorable outcomes. They were developed through an intensive review process,
be-Table 1. Cooperative Cardiovascular Project Quality Indicators: Eligibility and Exclusion Criteria*
Aspirin prescribed during the hospitalization Eligible: all patients with confirmed AMI
Exclusions: patients who died or were transferred on the day of admission and those with evidence of bleeding on admission or during the hospitalization; history of bleeding, chronic liver disease, coagulopathy, platelet count,100 3 109/L; a serum creatinine level.265
µmol/L (3 mg/dL); history of peptic ulcer disease or a discharge diagnosis of an upper gastrointestinal tract disorder; hemoglobin,100 g/L or hematocrit ,0.30; allergy to aspirin; treatment with warfarin sodium on admission; metastatic cancer; or terminal illness Criterion: received aspirin during the hospitalization
Aspirin prescribed at hospital discharge
Eligible: all patients with a confirmed AMI discharged alive and not transferred
Exclusions: patients with evidence of bleeding on admission or during the hospitalization; history of bleeding, chronic liver disease, coagulopathy, platelet count,100 3 109/L; a serum
creatinine level.265 µmol/L (3 mg/dL); history of peptic ulcer disease or a discharge diagnosis of an upper gastrointestinal tract disorder; hemoglobin,100 g/L or hematocrit ,0.30; allergy to aspirin; treatment with warfarin; metastatic cancer; or terminal illness Criterion: discharged and taking aspirin
Reperfusion using either thrombolytics or primary PTCA during first 12 h of hospitalization
Eligible: all patients with a confirmed AMI and not transferred from another hospital or emergency department
Exclusions: patients without ST-segment elevation or AMI on their admission electrocardiogram; with an onset of chest pain greater than 6 h prior to admission or inadequate documentation of the chest pain; chronic liver disease, history of bleeding, peptic ulcer disease, surgery in the past month, recent trauma, recent cardiopulmonary resuscitation; coagulopathy; any evidence of bleeding on admission; warfarin on admission; a history of stroke; older than 80 y; documentation that thrombolysis was considered but the physician or patient decided against it; or cardiac catheterization performed within 12 h of arrival without PTCA (assumed to be an aborted PTCA)
Criterion: received thrombolytics or PTCA within 12 h of arrival at the hospital b-Blocking agents prescribed at hospital discharge
Eligible: all patients with a confirmed AMI discharged alive and not transferred
Exclusions: good candidates: hypotension or shock during the hospitalization or systolic blood pressure at discharge of,100 mm Hg; history of asthma or chronic obstructive pulmonary disease; bradycardia or pulse at discharge of,50/min (unless discharged and taking a b-blocker); diagnosis of depression or treatment with antidepressants; dementia; conduction disorder including second- or third-degree heart block, bifasicular or trifasicular block; or those at very low risk as documented by no recurrent chest pain, no arrhythmias, no previous AMI, a normal stress test, and no LVEF,50%
Additional exclusions for ideal candidates: LVEF,35%, pulmonary edema or congestive heart failure (unless measured LVEF.50%), or treatment with insulin
Criterion: discharged and taking ab-blocker ACE inhibitors prescribed at hospital discharge
Eligible: all patients with a confirmed AMI and an LVEF,40% discharged alive and not transferred
Exclusions: patients with aortic stenosis; an allergy or intolerance to ACE inhibitor; a serum creatinine level.176 µmol/L (2 mg/dL); or a systolic blood pressure ,100 mm Hg at discharge
Criterion: discharged and taking an ACE inhibitor
Calcium channel blocking agents withheld at hospital discharge in patients with impaired left ventricular function
Eligible: all patients with a confirmed AMI and an LVEF,40% discharged alive and not transferred
Exclusions: patients with atrial fibrillation at any time during the hospitalization; recurrent chest pain; or those receiving calcium channel blockers prior to admission
Criterion: calcium channel blocker not prescribed at discharge Smoking cessation advice given to current cigarette smokers
Eligible: all cigarette smokers discharged alive and not transferred Exclusions: none
Criterion: documentation in the chart of advice or counseling on smoking cessation *AMI indicates acute myocardial infarction; PTCA, percutaneous transluminal angioplasty; LVEF, left ventricular
ginning with the establishment of a joint Health Care Financing Administration and American Medical Association Steering Committee for the CCP. Indicators were based on treatment guidelines for AMI published by the American College of Car-diology, the American Heart Association, and expert consensus.3Representatives from the American College of Cardiol-ogy, the American Academy of Family Practice, and the American College of Phy-sicians reviewed and refined these indi-cators. The peer review organizations in the 4 pilot states further refined the qual-ity indicators and developed data collec-tion instruments and computer algo-rithms.9,10
For each indicator, specific criteria de-termined whether a patient could have been a candidate for a particular interven-tion.Potentialcandidatesweredividedinto 2 subgroups. Ideal candidates are patients for whom the treatment would almost al-ways be indicated, and less-than-ideal can-didates are patients for whom the therapy was controversial (eg, the use ofb-blocking agents for patients with congestive heart failure), for whom it was contraindicated (eg, thrombolytics for patients with a re-cent hemorrhagic stroke), or for whom critical data for determining the appro-priateness of the intervention were miss-ing (eg, data on thrombolytic timmiss-ing were missing). Detailed information on the vari-able definitions, the indicator algorithms, and the data abstraction software are avail-able at the CCP World Wide Web home page (www.usccp.org).
Data were obtained from the medical record by trained abstractors employed by independent contractors. Quality was monitored and maintained by random reabstractions and the percentage of agreement was generally high (range, 94.8%-98.3%).11
Geographic Analysis and Statistical Methods
All Medicare records of hospitalizations of patients residing in the 50 states for 1995 and 1996 were used to assign each ZIP code in the United States to 1 of 3436 geographically distinct HSAs based on where the plurality of patients traveled for hospital care. Based on patterns of care
Figure 1. Geographic Variability in Performance of Quality Indicators
80 to 100 60 to < 80 40 to <60 20 to <40 0 to <20 Insufficient Data/ Not Populated A B C
A, Aspirin use during hospitalization; B, aspirin prescribed at discharge; C, reperfusion: thrombolytics or per-cutaneous transluminal coronary angioplasty. Maps reflect percentage of patients judged to be ideal candi-dates for receiving treatment by hospital referral region. Data are from the Center for the Evaluative Clinical Sciences, Dartmouth Medical School and from the Northeast Health Care Quality Foundation.
for major cardiovascular surgery, HSAs were aggregated into 306 HRRs.5The HRRs were empirically derived re-gional health care markets. The CCP data were mapped to these markets using the ZIP code of the institutional provider of care for each episode of myocardial in-farction. Details of the geographic analy-sis methods have been published.5Data from sparsely populated areas were pressed in these analyses. We also sup-pressed rates of adherence to specific in-dicators for any HRR that had less than 11 ideal cases for the indicator.
Quality indicators were evaluated only for patients during their first confirmed AMI during the sampling time frame and who were judged ideal candidates for a specific treatment (TABLE1). Rates of ad-herence to performance indicators (ie, the proportion of ideal patients with con-firmed AMI who received the specified
treatment) were calculated for each of 306 HHRs. These proportions were ad-justed for age and sex using logistic re-gression analysis.12The 20th and 80th percentiles were contrasted as a mea-sure of variability.13Standard statistical methods were used for the calculation of the correlation coefficient.14
RESULTS
The data set used in these analyses sists of 186 800 patients with con-firmed AMI. FIGURE 1 and FIGURE2
show the geographic variation in perfor-mance for each of the 7 CCP quality in-dicators. The white lines on the map are the state boundaries, and the black lines indicate the boundaries of the HRRs. Five levels of color intensity indicate the per-centage of ideal patients with con-firmed AMI receiving the therapy de-scribed by the quality indicator, ranging
from white (0%-20% of patients re-ceived the therapy) to red (80%-100%). The gray coloring indicates sparsely populated areas or those in which there are insufficient data to cal-culate meaningful rates. The overall rates of adherence to these quality indicators are summarized in TABLE2.
More than 90 000 patients were judged ideal for aspirin therapy, and it was widely prescribed during hospitalization (Fig-ure 1, A). The mean rate was 86.2% (range, 67.8%-100.0%) with 20th and 80th percentiles of 82.6% to 90.1%. No HRRs had rates less than 60%, and the majority were greater than 80%. Most of the HRRs with rates of 60% to 79% were in the south central and southeast re-gions. Aspirin was prescribed at hospital discharge in 77.8% of the approxi-mately 60 000 patients judged ideal for this therapy (Figure 1, B). The range was
Figure 2. Geographic Variability in Performance of Cooperative Cardiovascular Project Quality Indicators
80 to 100 60 to < 80 40 to <60 20 to <40 0 to <20 Insufficient Data/ Not Populated A C B D
A,b-Blockers prescribed at discharge; B, angiotensin-converting enzyme inhibitors prescribed at discharge; C, calcium channel blockers withheld at discharge; D, smok-ing cessation counselsmok-ing at discharge. Percentage of patients considered ideal candidates for receivsmok-ing treatment or smoksmok-ing cessation advice by hospital referral re-gion. Data from the Center for the Evaluation Clinical Sciences, Dartmouth Medical School and from the Northeast Health Care Quality Foundation.
between 52.1% and 96.0% with 20th and 80th percentiles of 72.5% to 83.9%. Ap-proximately half of the HRRs had rates more than 80%, and only a few were less than 60%. Highest rates were observed in the northeast, north central, and moun-tain regions.
The quality indicator for reperfusion includes treatment with thrombolytic agents or primary percutaneous translu-minal coronary angioplasty during the first 12 hours of hospitalization. The mean rate of reperfusion among 17 071 ideal patients was 67.2% (Figure 1, C). Substantial varia-tion was found with a range from 33.0% to 93.3% and 20th and 80th percentiles of 59.8% to 75.1%. Lowest rates were in the south central and mid Atlantic states with a few HRRs in the west and north-west. Rates greater than 80% were ob-served in 23 widely scattered HRRs.
There were many exclusions for the use ofb-blocking agents, thus only 14 839 (7.9%) of the 186 800 patients with con-firmed AMI were judged ideal for this treat-ment. The large number of HRRs in Min-nesota with insufficient data is a consequence of the smaller proportion of AMI patients sampled in that state. Ap-proximately half (49.5%) of all patients judged ideal receivedb-blocking agents (Figure 2, A). The range was 0%-92.7% with 20th and 80th percentiles of 35.8% to 61.5%. Rates of use ofb-blocking agents were highest in the northeast and north central regions and lowest in the south cen-tral and south east regions.
Angiotensin-converting enzyme (ACE) inhibitors were prescribed to 59.3% of the approximately 18 000 patients judged ideal for this treatment (Figure 2, B). The
range of rates is wide (6.7%-100%) with 20th and 80th percentiles of 49.2% to 69.2%. Rates were somewhat higher in the north central region, but there was no clear geographic pattern of ACE inhibitor use. The quality indicator for calcium chan-nel blocking agents specifies that they be withheld from patients with impaired left ventricular function (ejection fraction ,40%). Since only 4.8% of the patients had this degree of impairment of ven-tricular function, approximately 25% of HRRs had insufficient data on which to base adherence rates for this quality in-dicator. Overall, calcium channel block-ing agents were withheld from 81.9% of patients for whom their use was contra-indicated. There was little variability in rates with 20th and 80th percentiles of 73.6% to 90.8% and no clear geo-graphic pattern (Figure 2, C).
Of the 186 800 patients with con-firmed AMI, 22 024 (11.8%) were iden-tified in the clinical record as current ciga-rette smokers. Of these, 41.9% have documented evidence of smoking sation advice. The rates of smoking ces-sation advice varied widely (7.3%-81.7%) with 20th and 80th percentiles of 32.8% to 51.3% (Figure 2, D). Rates were highest in Alaska and the moun-tain states and lowest in the south cen-tral and southeast regions.
Toexploretheeffectsofchance,westrati-fied the 306 HRRs into tertiles based on the observed sample size. We calculated the mean and the 20th and the 80th percen-tiles for small, medium, and large HRRs. These results (not shown) were similar in the small, medium, and large HRRs for ev-ery quality indicator. Furthermore, there
were only relatively small differences in the 20th and the 80th percentiles of the esti-mates for the quality indicators.
We also examined the correlation be-tween the various quality indicators by HRR. There was a significant positive cor-relation between the indicators for treat-ment with aspirin,b-blocking agents, and ACE inhibitors (r = 0.26-0.59; all P val-ues,.001). Smoking cessation advice was also positively correlated with these indicators (r = 0.16-0.27; all P values ,.01). The withholding of calcium chan-nel blocking agents among patients with impaired left ventricular function was weakly and inconsistently related to the other quality indicators. Reperfusion was not significantly correlated with any of the other quality indicators.
COMMENT
In these analyses, based on 186 800 pa-tients treated for a confirmed AMI and judged “ideal” for the specific treatment, we found considerable variability in the rates of adherence to the CCP quality in-dicators. Aspirin was used frequently both during hospitalization (86.2%) and at dis-charge (77.8%), and calcium channel blocking agents were withheld from most patients with impaired left ventricular function (81.9%). Lower rates were seen in the use of ACE inhibitors at discharge (59.3%), reperfusion using thrombo-lytic therapy or coronary angioplasty (67.2%), prescription ofb-blocking agents at discharge (49.5%), and for docu-mented smoking cessation advice (41.9%). Quality indicators for aspirin, b-blocking agents, ACE inhibitors, and smoking cessation advice were
posi-Table 2. Rates of Performance of Cooperative Cardiovascular Project Quality Indicators Among Ideal Patients With Confirmed Acute Myocardial Infarction*
Quality Indicator No. of Ideal Patients Mean, % Range, % 20th-80th Percentiles Aspirin prescribed during the hospitalization 96 246 86.2 67.8-100.0 82.6-90.1
Aspirin prescribed at hospital discharge 60 044 77.8 52.1-96.0 72.5-83.9
Reperfusion using either thrombolytics or primary PTCA during first 12 h of hospitalization
17 071 67.2 33.0-93.3 59.8-75.1
b-Blocking agents prescribed at hospital discharge 14 839 49.5 0-92.7 35.8-61.5 Angiotensin-converting enzyme inhibitors prescribed
at hospital discharge
18 114 59.3 6.7-100.0 49.2-69.2
Calcium channel blocking agents withheld at hospital discharge in patients with impaired left ventricular function
9083 81.9 42.7-100.0 73.6-90.8
Smoking cessation advice given to current cigarette smokers 22 024 41.9 7.3-81.7 32.8-51.3 *PTCA indicates percutaneous transluminal angioplasty.
tively correlated within HRRs. There was substantial geographic variation in the treatment of AMI. A wide range of treat-ment rates by HRR was found for most of the quality indicators. This data set does not have information on any health sys-tem characteristics, but the observed geo-graphic variability observed does not sup-port the existence of systematic effects. High and low rates of quality indicators can be found within the same state or gion. Although some rather striking re-gional variations exist, much of the ob-served variability seems to relate to local clinical practices. It is unlikely that this variation between the care described by the quality indicators and the kind of care actually provided is a consequence of chance or of differences in patient case mix in this large population of patients ho-mogeneous with respect to age, sex, and access to health care.
There are 2 limitations to these data and the inferences that can be drawn from this study. First, these data rely on informa-tion contained in the medical record. Medical records are sometimes illegible or poorly organized, and the task of medi-cal record abstraction is quite difficult. Re-liability testing of the medical record ab-straction in the CCP study has shown excellent interrater reliability. While it is possible that variations noted were due to care that was provided and not docu-mented, this would suggest a significant departure from established documenta-tion policies. In all hospitals, it is quired that physician orders be re-corded in the medical record for specific therapies to be administered, and docu-mentation of discharge medications is re-quired by the Joint Commission on Healthcare Organizations. Thus, we be-lieve that the CCP data abstraction sys-tem yields an overall accurate represen-tation of the care of these patients. Second, the patterns of geographic variation in the treatment of AMI observed in this na-tional study may accurately represent care during this study period but may not rep-resent long-term patterns of care.
Prior studies have shown variability in use of medical and surgical services.15,16 Studies of treatment of AMI have evalu-ated variability in the use of diagnostic
and therapeutic procedures among spe-cific patient subgroups, by payers, or by location.17-20Studies of specific medical therapies have been far less frequent. Pi-lote et al21studied regional variation in the management of AMI in the United States among 21 772 patients and found substantial variation in the use of medi-cations and in invasive procedures. Rog-ers et al22reported observations from the National Registry of Myocardial Infarc-tion and concluded that there was sub-stantial underuse of thrombolytic therapy andb-blocking agents and substantial overuse of calcium channel blockers.
Reports from randomized trials or vol-untary registries may not represent the care provided for the entire United States. The CCP results describe AMI care for pa-tients with AMI participating in the Medi-care fee-for-service program. These find-ings are in general agreement with the conclusions reached by Pilote et al21and Rogers et al22and extend the findings of these studies by identifying patients ideal for the specific therapy and demonstrat-ing variation in compliance to guide-lines throughout the United States. This study shows the opportunity for improve-ment of the care of patients with AMI us-ing existus-ing knowledge. Aspirin, b-blocking agents, ACE inhibitors, and thrombolytics have been shown in ran-domized trials to reduce mortality due to AMI.23-25Reperfusion using percutane-ous transluminal coronary angioplasty has been shown to have a protective effect on short-term mortality after AMI.26The American College of Cardiology and American Heart Association guidelines27 have listed primary percutaneous trans-luminal coronary angioplasty as an alter-native to thrombolytic therapy. In these CCP data, substantial numbers of pa-tients judged ideal for these treatments did not receive them. Approximately 14% of such patients did not receive aspirin during hospitalization, 22% did not receive aspirin at discharge, 50% did not receiveb-blocking agents, 41% did not receive ACE inhibitors, and 33% did not receive reperfusion. Calcium channel blocking agents were admin-istered to 18.1% of patients with im-paired left ventricular function.
Cur-rent guidelines generally recommend against the use of calcium channel blocking agents in the acute or long-term care of patients with AMI.27There was no documentation that 58% of patients who smoke received smoking cessation advice.
The CCP quality indicators are prac-tice guidelines based largely on evidence from randomized clinical trials and were not controversial at the time this study was conducted. They describe practices of care that will optimize patient outcomes and reduce the use of possibly harmful thera-pies.28Why then does this gap between the care provided and the quality indica-tors exist? Physicians may be unaware of the guidelines or disagree with their con-tent29; or they may be resistant to guide-lines because they perceive the loss of pro-fessional autonomy.30,31 Alternatively, changes in behavior lag behind knowl-edge.32It is likely that all of these factors contribute to the lack of uniformity of treat-ment observed in this study. Improvetreat-ment of clinical care is possible. Feedback of the CCP data to hospitals improved clinical care in the 4 pilot test states33; local medi-cal opinion leaders are successful in ac-celerating the rate of improvement of AMI management34; and techniques of continu-ous quality improvement are useful to change current clinical practices.35-37
These gaps between knowledge and practice have important consequences. Acute myocardial infarction is a com-mon and serious condition, and the evi-dence from clinical trials strongly sug-gests that adherence to these established guidelines will result in better patient out-comes. It is undoubtedly true that some AMI patients experience unnecessary mor-bidity or mortality because they receive substandard medical care. This study finds that there is currently unrealized poten-tial for more effective care of patients with AMI. Using the lessons learned from stud-ies such as the CCP to improve continu-ally the outcomes of cardiovascular care is a goal that should be shared by soci-ety, payers, and clinicians. Because these goals are primarily the responsibility of cli-nicians, it is essential for the public good that clinicians shoulder that responsibil-ity by improving the qualresponsibil-ity of care.
Disclaimer: Opinions in this article should not be taken as the official position of the Health Care Financing Administration.
Funding/Support: All support for this study was pro-vided by the Health Care Financing Administration, Baltimore, Md.
Resources: ZIP code groupings are in the public do-main and may be obtained from Patricia Helm ESRI, Redlands, Calif (e-mail: [email protected]) by request-ing the Health Data Sampler.
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The circle of science which I have run through, before I undertook the study of physic, is not only useful but absolutely necessary to the making of a skilful physi-cian. Such sciences enlarge our understanding, and sharpen our sagacity; and what is a practitioner with-out both but an empiric, for never yet was a disorder found entirely the same in two patients?
