CHAPTER 2: Measuring Quality

KEY POINTS

• Quality is defined 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.”

• The ability to measure quality is an essential component to improve quality of care.

• Quality of care has multiple domains and no single metric can appropriately define quality.

• Quality indicators should represent metrics that have face validity and are actionable by patients, clinicians, and managers.

• Methodological rigor is necessary to avoid spurious interpretations and provide proper interpretation of quality metrics.

• Public reporting quality metrics can have unintended consequences to the health care system.

• Quality metrics can be divided into outcome metrics, process metrics, and structural metrics.

• Quality metrics that are based on outcomes are widely used to compare health care systems, but are not necessarily sensitive or specific to identify outliers and may lead to biased conclusions.

• When rigorously and objectively defined, quality metrics that are based on processes of care can be more informative on specific aspects of quality.

• Many structural aspects of ICUs are associated with quality, but it is possible for ICUs that do not have these attributes to still perform with high quality.

DEFINING QUALITY

The definition of quality depends on the field being evaluated. For example, although they each provide food and housing, the definitions for high-quality hotels, prisons, and hospitals will be considerably different. The International Organization for Standardization defines quality broadly as “the totality of features and characteristics of a product or service that bears on its ability to satisfy stated or implied needs” (ISO 8402–1986 standard). In health care, quality has been abstractly defined 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.”¹ Although a bit vague, this definition emphasizes two challenging aspects of measuring the quality of health care: (1) the need to improve outcomes and (2) the importance of evidence. Throughout this chapter, we will focus on these two concepts to discuss measuring quality through evidence-based processes of care that should ultimately lead to improved outcomes.

WHY DO WE MEASURE QUALITY?

“Count what is countable, measure what is measurable, and what is not measurable, make measurable” is frequently attributed to Galileo.² The ability to manage outcomes or processes of care is fundamentally tied to being able to measure them. Finding clinically relevant, measurable, and actionable outcomes and processes in health care is necessary to provide clinicians with the ability to improve their systems. This is not to say that all important determinants of quality can be measured or that those that cannot be measured should be ignored. Deming, the grandfather of quality metrics, once stated that “running a company on visible figures alone” is one of the seven deadly sins of management.³ However, to demonstrate improvement or ...