Measuring up to medication safety
From the March 10, 2005
Medications are among the most common interventions
used to improve health. So it should come as no surprise that
adverse drug events injuries caused by the use of medications
are a substantial source of preventable harm to hospitalized
patients. Measuring the level of safety is fundamental to
improvement. Yet, measuring medication safety has long been
a conundrum. Historically, measurement efforts have focused
on practitioner reporting of medication errors, which, at
best, uncovers just a fraction of the errors, most of them
harmless. Still, measurement is the only way to answer these
Do we have a problem?
What is the extent of the problem?
Have improvement efforts been successful?
How do we compare to others?
There are four types of measures that should be tracked
if you want to improve medication safety.
Process measures. These measures help assess how
well you are performing core processes associated with medication
use. Measuring core processes helps determine if there is
variation in carrying them out, which could lead to undesirable
outcomes, and if there are preventable risks associated
with processes, which could result in harm. Process measures
can be identified for all facets of medication use. However,
high-volume and high-risk processes, or processes associated
with high-alert medications, should be targeted to maximize
the benefit to patient safety. A few examples include:
One newly evolving measure to evaluate improvement within
a process is to track the total risk priority number (RPN)
of a process that has undergone a failure mode and effects
analysis. As an organization works to improve the process,
the RPN should decrease over time as effective changes are
implemented. For more information on this process measure,
visit www.ihi.org (click
on Topics, Patient Safety, Medication Systems, Measures).
Structure measures. These measures assess the organizational
culture, values, and leadership. They differ from process
measures in that they are not task oriented, but foundational
in nature. Examples include:
The Agency for Healthcare Research and Quality (AHRQ) has
recently released a new, tested survey for assessing the
safety culture in hospitals. The tool also offers guidance
on sampling, data collection, and analysis of findings (see
Outcome measures. These measures assess whether
your efforts to improve medication safety have been successful.
As such, many believe that medication errors are the most
useful outcome measure for medication safety. However, harm
is a much more reliable and powerful measure, especially
if it keeps you intellectually engaged with the possibility
that all harm is preventable.
If errors are used to measure medication safety, self-reporting
is the typical data-gathering tool, which is highly inaccurate.
Errors are the obvious focus, so any adverse drug events
uncovered are quickly sorted into preventable and non-preventable
categories. This, in turn, promotes the tacit acceptance
of non-preventable harm as a property of the
medication system, something for which you have no responsibility.
On the other hand, if harm is used as a measure of medication
safety, the measure is reliable, clear, and direct, and
the focus is on all unintended results. This keeps you intellectually
engaged with the possibility of reducing all patient harm,
to admit that you can do better, to raise the bar when it
comes to patient safety. For example, most hospitals collect
data on readmissions to the hospital. If bleeding episodes
from warfarin caused some of the readmissions, these events
may not be fully assessed if the focus is on errors alone.
In these cases, errors may not be apparent, so the events
would likely be tagged as non-preventable adverse
drug reactions. But if focused only on preventing harm in
patients who take warfarin, not error, youre more
likely to explore ways to reduce all occurrences of bleeding.
Thus, the best outcome measure for medication safety is
all adverse drug events, regardless of causation.
Evaluating patient records using a list of triggers is
the most effective means of collecting data on adverse drug
events. Triggers are clues that an adverse drug event may
have occurred. Follow up is needed for confirmation. An
extensive list of triggers can be found here.
Computerized methods for detecting adverse drug events
via a trigger tool have proved very effective (Classen DC,
Metzger J. Improving medication safety: the measurement
conundrum and where to start. Internat Jour for Qual
in Health Care
2003; 15:i41-i47). However, this methodology
requires a high level of automation with customized software
linkage to clinical databases, so the initial outlay may
be costly. However, recently, a relatively low cost, low
tech method for using a trigger tool to uncover adverse
drug events has been devised and tested in more than 80
hospitals (Rozich JD, Haraden CR, Resar RK. Adverse drug
event trigger tool: a practical methodology for measuring
medication related harm. Qual Saf Health Care
12;194-200). The technique, which requires minimal training,
appears to increase the rate of adverse drug event detection
50-fold over traditional reporting methodologies.
Balancing measures. These measures are used to ensure
that a change in one part of the system is not causing problems
in another part of the system. For example, by using balancing
measures, one hospital quickly learned that a change in
antiemetics to reduce the time a patient must spend in the
oncology clinic actually resulted in reduced patient satisfaction.
Patients felt rushed and unable to talk to staff about their
diagnosis and therapy.
Measuring medication safety is not easy, but it must be
a core component of your improvement efforts. If you do
not have an effective measurement plan in place, an interdisciplinary
team should consider the examples above and identify a place
to start. Be sure to clearly describe each measure, its
goal, and the data collection plan. Remember: traditional
efforts to measure medication safety have not been successful
in guiding improvement. Thus, even if you currently have
a measurement plan in place, it may be time to look at it
again with fresh eyes and updated tools.