207Sinai Hospital (New York City, New York) by using RCA to address a patient care
issue [ 66 ]. Residents attended a QI conference every 4 weeks during which a pre-
selected teaching case was presented. A resident on an elective or outpatient block
was chosen to investigate the case and gather relevant details in the weeks prior to
the session. During the session, chief residents and faculty members facilitated a
group discussion with a focus on identifying system-wide failures and solutions.
Over the course of 22 months, 46 interventions were suggested, 25 of which were
initiated and 18 of which were determined to be successful. The authors noted that
“empowering residents to take a more active role in performance improvement
yields significant change and does more than simply educate about basic QI meth-
odology.” They also aptly pointed out that residents are key frontline providers who
spend the most time working within clinical care systems and can therefore provide
important insight into areas that need improvement. An important observation the
authors also made was that suggestions were more likely to advance if administra-
tors with decision-making authority were present.
For institutions that are limited on time or resources to individualize a QI project,
authors from Vanderbilt University Medical Center (Nashville, Tennessee) advocate
using the traditional morbidity and mortality conference as a means of establishing
a culture of safety while teaching the ACGME general competencies. In their pub-
lication, they described retrospectively reviewing morbidity and mortality cases that
had been presented [ 38 ]. They identified seven categories that were then evaluated
to see which of the six ACGME general competencies were addressed. During a
21-month period, 11 cases were discussed, which generated 23 QI initiatives. The
initiatives were classified as procedure related, process related, patient related, com-
munication error, medication error, ethics related, and device related. Several other
authors have reported similar success with the application of an RCA to morbidity
and mortality conferences [ 5 , 58 , 59 ].
Six Sigma and Lean Methodology
Six Sigma is a QI strategy invented by Motorola, Inc. (Schaumburg, Il) in the 1980s,
named after the statistical measure of variation, sigma, which is the standard devia-
tion of a normal distribution [ 14 ]. The concept of Six Sigma reflects the number of
standard deviations that it takes to achieve an error-free rate of 99.9996%. In manu-
facturing, a level of Six Sigma is equivalent to less than 3.4 defects per million units
produced, a concept referred to as defects per million opportunities (DPMO). A
defect rate can be defined by any measure that is relevant to the process being
improved. Setting the goal to achieve a Six Sigma strategy does not guarantee
achievement of that goal but does lay the groundwork for improvement. The field of
surgical anesthesia serves as a good example of the application of this principle. In
the 1970s–1980s, the risk of death related to anesthesia was 1 in 10,000–20,000 – or
25 to 50 per million [ 29 ] – but through the advent of several QI measures, that risk
has decreased to 1.1 per million [ 45 ].
Lean methodology stems from the Toyota Production System created by Toyota
Motor Corporation engineer Taiichi Ohno in the 1950s [ 84 ]. He revolutionized the
automotive production system by focusing on eliminating inefficiency and waste,
11 The Role of Educators in Quality Improvement