WHAT IS QUALITY?
More than 30 years ago, Donabedian[22]
proposed that we measure the quality of health care by observing its structure, processes,
and outcomes. The IOM has defined health care quality
in the United States 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."[23]
The IOM's
definition and framework incorporate two of Donabedian's three elements in a broad
approach to measuring health care quality: determining effects of health care on
desired outcomes, including a relative improvement in health and in consumers' evaluations
or experience of health care, and assessing the degree to which health care adheres
to processes proved by scientific evidence or agreed by professional consensus to
affect health or that concur with patients' preferences.
Although efforts to evaluate how the structure of care affects
patient outcomes have been limited, evidence regarding the impact of intensive care
unit (ICU) organizational characteristics on patient safety and on quality of care
is fairly well developed. There is significant evidence to support the association
between ICU physician and nurse staffing and mortality, complications, and length
of stay.[11]
[24]
To help provide feedback regarding the quality of care provided,
varied audiences need health care quality measures that they can use for health care
purchasing, regulatory accreditation and monitoring, or performance improvement.
[25]
[26]
[27]
For all these purposes, it is imperative that quality measures be important, scientifically
sound, usable across settings, and feasible.
Measures of processes and outcomes are the lenses through which
we can see the quality of care we provide. Looking at independent measures of quality
may not give us the whole picture, but if we put all the measures together, we get
a more accurate picture of quality. Quality measures, like the pictures, help us
to know the quality of care provided from a variety of different perspectives. Through
each picture, we get to know the many facets of quality. As such, it may be more
appropriate to refer to the qualities of care we
provide.
The IOM has further suggested some categories for these qualities
of care. Health care should be safe, patient-centered, timely, efficient, and equitable.
[5]
[25]
[28]
Whereas the aims of effectiveness and safety of health care are nearly universal,
societies and cultures around the world differ in how much they emphasize the additional
aims of patient-centeredness, timeliness, efficiency, and equity. This avails those
seeking to improve with a wider spectrum of dimensions on which to customize their
improvements. Process of care measures of quality assess whether providers perform
health care processes that achieve the desired aims and avoid those processes that
predispose to harm.
Because the goal of measurement is to learn and improve, the measurement
system must fit into an improvement system. Briefly, we find it useful to assume
that there are three key components of this system. First, there must be the will
among caregivers to work cooperatively to improve. Second, there must be ideas or
hypotheses about changes to the current system of care. Third, the team must have
a model for testing changes and implementing those that result in improvements.[29]
As such, the ability to measure, to know if a change is an improvement, is fundamental
to any improvement system.[30]
Although the ideas
of quality measures discussed previously apply to groups of patients, many of the
efforts to improve patient safety are targeted at individual patients.
