The Quality Alliance Steering Committee (QASC) is a broad-based coalition of physicians, consumers, purchasers, health insurance plans and others who seek to improve health care quality and patient safety through a collaborative process in which key stakeholders agree on a strategy for measuring performance at the physician or group level; collecting and aggregating data in the least burdensome way; and reporting meaningful information to consumers, physicians and other stakeholders to inform choices and improve outcomes.

The term "quality care" is defined differently by various health care system stakeholders.  NBCC defines quality care as a patient-centered, evidence-based system of care that fulfills the following overlapping core values:  access, information, choice, respect, accountability, and improvement.  The IOM defines quality as "the degree to which health services for individuals and populations increase the likelihood of desired health outcomes and are consistent with current professional knowledge."  Quality care is not to be confused with quality of life.  While both concepts can be used at the individual level, only quality care can also be used at the health care system level.

Quality improvement is a process for identifying and measuring deficiencies in health care that will motivate change.  Quality improvement efforts are typically for internal use by health care providers, and/or hospital or health plan administrators and the data collected are not reported publicly.

An evidence-based standard of care against which adherence can be ascertained.  Quality indicators should be linked to improved patient outcomes.  A quality indicator becomes a quality measure in the act of measuring adherence to the standard.

A quality measure is a mechanism that quantifies the quality of a selected aspect of care by comparing it to an evidence-based standard of care (quality indicator).  The three types of quality measures include outcome measures which reflect the impact of an intervention on the patient's health status, process measures which assess the degree to which a health care provider delivers appropriate and timely care, and structural measures which capture characteristics of a health care delivery system and its capacity.  All quality measures must be scientifically sound, important, usable, and feasible to implement.

Quality of life is a multi-dimensional, subjective assessment of an individual's well-being.  Quality of life can include physical and mental health, and can capture an individual's satisfaction with and enjoyment of relationships with family and friends (social health).  Quality of life may be defined in many different ways.  This makes measuring and monitoring changes in quality of life very difficult.