Frederick A. Masoudi, John S. Rumsfeld
Measurement and Improvement of Quality of Care
Relevance to Cardiovascular Clinical Practice
Although the quality of health care is important for all stakeholders, the primary perspective of this chapter is that of cardiovascular clinicians. Our goals are to help cardiovascular clinicians understand the definition and importance of quality of care, and the relevance of quality of care measurement and improvement in current cardiovascular practice. We focus on measuring health care quality and uses of quality measurements, as well as improving quality of care, with examples of quality improvement (QI) approaches.
Defining Quality of Care
Quality of care generally is defined as the extent to which health care delivery optimizes the outcomes, or the “end results,” of care. In the United States, the Institute of Medicine (IOM) has more specifically defined quality of care as “the degree to which health care systems, services, and supplies for individuals and populations increase the likelihood for desired health outcomes in a manner consistent with current professional knowledge.”1 Key outcomes of care include survival, patient health status (i.e., symptom burden, functional status, and health-related quality of life), morbidity (e.g., acute myocardial infarction [MI] or heart failure hospitalization), patient experience (e.g., satisfaction), and cost-effectiveness.
The IOM has further proposed six domains of quality (Table 5-1), specifying that high-quality health care is effective, safe, equitable, timely, efficient, and patient-centered. Quality of care can thus be conceptualized as the extent to which these domains are optimized to improve outcomes of care. Accordingly, quality measures either should focus on at least one of these six domains of quality or should directly measure outcomes of care. QI is the action undertaken to improve one or more of these six domains in order to improve health outcomes.
TABLE 5-1
Institute of Medicine Domains of Highest-Quality Health Care
QUALITY DOMAIN | BRIEF DEFINITION |
Effective | Providing services based on scientific knowledge to all who could benefit and refraining from providing services to those not likely to benefit (avoiding underuse and overuse, respectively) |
Safe | Avoiding harm to patients from the care that is intended to help them |
Equitable | Providing care that does not vary because of personal characteristics such as sex, ethnicity, geographic location, and socioeconomic status |
Timely | Reducing waits and sometimes harmful delays for both those who receive care and those who give care |
Efficient | Avoiding waste, including the waste of resources and patient time, as well as waste of equipment, supplies, ideas, and energy |
Patient-centered | Providing care that is respectful of and responsive to individual patient preferences, needs, and values, and ensuring that patient values guide all clinical decisions; this type of care attends to patients’ physical and emotional needs, maintaining or improving their quality of life, and gives them the opportunity to be the locus of control in decision making. |
From Institute of Medicine, Committee on Quality Health Care in America: Crossing the Quality Chasm: A New Health System for the 21st Century. Washington, DC, National Academies Press, 2001.
Unfortunately, despite tremendous therapeutic advances in the past 50 years, well-recognized deficiencies in health care delivery are manifest, as suboptimal quality and outcomes of care persist. Health care spending in the United States exceeds that of any other country, but American health care does not achieve commensurately high scores on most metrics of quality of care or health outcomes.2 Marked geographic variation in per capita health care utilization and spending are well recognized, yet consistent correlation between spending and health outcomes is lacking. For example, significant variation in the use of cardiovascular testing and procedures that is not explained by case-mix does not clearly translate into better patient outcomes.3
Numerous studies have documented underuse of guidelines-indicated care, unexplained variation in care delivery, and outcomes that may reflect overuse or inconsistent quality of care delivery, and misuse, including avoidable complications and medical errors, all of which contribute to suboptimal outcomes. Gaps in quality can result from deficiencies in any of the IOM quality domains (see Table 5-1). For example, effective therapies may not be provided to eligible patients (e.g., statin therapy in a patient with a recent MI). Providers and health care systems may fail to minimize exposure of patients to unnecessary risk (e.g., prescribing drugs that carry a high risk of adverse drug-drug interaction). Clinicians may prescribe suboptimal or ineffective therapies (e.g., routine primary-prevention implantable cardioverter-defibrillator placement in a patient with mild left ventricular systolic dysfunction) or may recommend use of resource-intensive care for marginal benefit (e.g., routine intra-aortic balloon pump use for high-risk percutaneous coronary intervention). Care delivery may be excessively delayed or may be delivered differentially based on patient age, sex, race/ethnicity, or insurance status. Patients may not be engaged in their care to focus principally on the health outcomes of highest import (e.g., quality of life in addition to quantity of life). Deficiencies in any of these areas contribute to observed variations in quality of care and patient outcomes. These deficiencies, coupled with rising health care costs, have raised interest in health care reform, in which measurement and reporting of quality of care are central to clinical practice.
Measuring Health Care Quality and Uses of Quality Measurements
This section discusses types of quality measures, the uses of measures, commonly used data sources for quality measurement, and possible limitations of quality measures, including the potential for unintended consequences.
Types of Quality Measures
Donabedian’s seminal treatise, published more than 50 years ago, delineated a conceptual framework for measuring health care quality that endures to the present: characterizing quality according to structure, process, and outcome.4 Although measurement has extended beyond these three domains, these constructs remain central to understanding the quality of health care. The American College of Cardiology/American Heart Association (ACC/AHA) have described in detail the methodologic principles of developing various types of measures.5–8
Structural measures are specific attributes of the health care delivery system that are used as surrogates for the care delivered. Examples are procedural volume and accreditation status. In general, such measures are only weak surrogates and frequently are considered inadequate if more robust metrics of quality are available.9,10
Process measures reflect the actions of providers, such as the prescription of a medication, and are among the most commonly used metrics of quality. For example, the Centers for Medicare & Medicaid Services (CMS) has used processes of care for acute MI and heart failure as part of its Hospital Compare quality reporting system since 199511; the ACC/AHA have developed several sets of process measures for specific cardiovascular procedures and conditions (Table 5-2). Operationally, process measures are generally selected from among the care processes with strong support in practice guidelines (e.g., class I recommendations in the ACC/AHA guideline recommendation taxonomy). Not all strong guideline recommendations are appropriate for adoption as quality measures, however; such measures should possess additional attributes that support their use for quality measurement (Table 5-3).
TABLE 5-2
Current American College of Cardiology/American Heart Association (ACC/AHA) Performance Measure Sets
TOPIC AREA | PUBLICATION YEAR (WITH UPDATE) | PARTNER ORGANIZATIONS |
Heart failure | 2005 (2011) | ACC/AHA (inpatient) ACC/AHA/AMA-PCPI (outpatient) |
Chronic stable coronary artery disease | 2005 (2011) | ACC/AHA/AMA-PCPI |
Hypertension | 2005 (2011) | ACC/AHA/AMA-PCPI |
ST-elevation and non-ST-elevation myocardial infarction | 2006 (2008) | ACC/AHA |
Cardiac rehabilitation | 2007 (2010) | AACVPR/ACC/AHA |
Atrial fibrillation | 2008 | ACC/AHA/AMA-PCPI |
Primary CVD prevention | 2009 | AHA/ACCF |
Peripheral artery disease | 2010 | ACCF/AHA/ACR/SCAI/SIR/SVM/SVN/SVS |
Percutaneous coronary intervention | 2013 | ACCF/AHA/SCAI/AMA-PCPI/NCQA |
Cardiac imaging | 2014 (est.) | ACCF/AHA/ACR/AMA-PCPI/NCQA |
AACVPR = American Association of Cardiovascular and Pulmonary Rehabilitation; ACCF = American College of Cardiology Foundation; ACR = American College of Radiology; AMA-PCPI = American Medical Association–Physician Consortium for Performance Improvement; CVD = cardiovascular disease; NCQA = National Committee for Quality Assurance; SCAI = Society of Cardiovascular Angiography and Interventions; SIR = Society of Interventional Radiology; SVM = Society of Vascular Medicine; SVN = Society of Vascular Nursing; SVS = Society of Vascular Surgeons.
TABLE 5-3
Attributes of Measures of Process, Outcome, and Value in Health Care
MEASURE TYPE | MEASURE ATTRIBUTES |
Process5 | Evidence-based |
Interpretable | |
Actionable | |
Explicit numerator and denominator | |
Valid | |
Reliable | |
Feasible | |
Outcomes6 | Clear explicit definition of appropriate patient sample |
Clinically coherent variables for risk adjustment | |
Sufficiently high-quality and timely data | |
Designated time of covariate and outcome ascertainment | |
Standardized period of outcome assessment | |
Analysis accounting for multilevel organization of data | |
Disclosure of methods used |