Quality Management
Determined from Risk Assessment
Bruce Thomadsen
University of Wisconsin
and
The Center for the
Assessment
of Radiological Sciences
Learning Objectives
To understand how to approach developing a QM
program from a risk analysis:
1.
Redesign to eliminate potential failures,
2.
Ensure resources and key core components,
3.
Fix environment and technical problems
4.
Commission well and add QC and QA
So, What to Do
After making the fault tree. What now?
n  Address the potential failures.
n
What to Do?
Start with the branches of the fault tree with either
highest PRN or S.
n  Wherever you start, you will consider all the possible
failure modes until prevention is not worth the
resources.
n  So, if you are off in your values for the FMEA, not a
big deal.
n  Pay particular attention to common causes.
n
Generalization about Fixes
The prevention of events can be by:
n  Eliminating progenitor causes,
OR
n  By interrupting the propagation.
Patient
Misidentified
X
Human error:
Omission - Time
out not performed
Or
X
Training - patient
identified
incorrectly
Redesign
n
The best way to avoid potential errors at some
step is to redesign the procedure so that error is
not possible (i.e., what leads to it no longer
exists).
Redesign
The best way to avoid potential errors at some
step is to redesign the procedure so that error is
not possible.
n  Re-evaluate after a redesign because new
possible errors may have been produced.
n
Possible Interventions
•
•
First correct any environmental
problems – that usually is a
relatively inexpensive but effective
operation.
Fix technical problems.
Possible Interventions 2
Then consider the key core components identified by
AAPM TG 100:
§
Standardized procedures
§
Adequate staff, physical and IT resources
§
Adequate training of staff
§
Maintenance of hardware and software resources
§
Clear lines of communication among staff
Possible Interventions 3
As you start with the highly ranked potential
failures, it is useful to consider all the given branch
of the fault tree at once.
n  It is also efficient to work though all the branch of
the process tree at once.
n  Work down through the rankings until you get to
potential failures that you don’t care if they happen
given your resources.
n
Commissioning
Identify those potential failures that can be
eliminated through commissioning.
n  This is likely to be many.
n
Inadequate or lack
of procedures /
practices
Defective
materials/tools/
equipment (2.1,
2.2, 2.3)
Commissioning
>3*sigma error
contouring errors:
wrong organ,
wrong site, wrong
expansions (1)
Don’t try to read!
User Error (2.5,
2.6)
366
Or
250
Inadequate design
specification (3.2)
Inadequate
assessment of
operational
capabilities (3.5)
Inadequate
programming (3.6)
Inattention,
Rushed process,
lack of time or
staff, fatigue,
failure to review
work
Inadequate or lack
of procedures /
practices
Taken care of by the generally complete
training, establishing clear communication
modalities (possibly forms) and
establishing protocols, policies and
procedures
255
Availability of
defective
materials/tools/
equipment (2.1,
2.2)
Materials/tools/
equipment used
incorrectly or
inadequate
assessment of
materials/tools/
equipment for task
(2.5, 2.6)
Excessive
delineation errors
resulting in <3*
sigma
segmentation
Errors (2)
Key item for commissing
326
Inadequate design
specification (3.2)
Or
Inadequate
assessment of
operational
capabilities (3.5)
Inadequate
programming (3.6)
260
Inadequate
training /
orientation (6.1)
Key item for facility managerial changes
Inattention,
Rushed process,
lack of time or
staff, fatigue,
failure to review
work
Inadequate or lack
of procedures /
practices
Availability of
defective
materials/tools/
equipment (2.1,
2.2)
Taken from TG 100
Error in
delineating
GTV/CTV (MD)
and other
structures for
planning and
optimization
Materials/tools/
equipment used
incorrectly or
inadequate
assessment of
materials/tools/
equipment for task
(2.5, 2.6)
Or
Poorly drawn
contours (spikes,
sloppy, etc) (3)
265
Inadequate design
specification (3.2)
212
Or
Inadequate
assessment of
operational
capabilities (3.5)
Inadequate
programming (3.6)
Inadequate
training /
orientation (6.1)
Inattention,
Rushed process,
lack of time or
staff, fatigue,
failure to review
work
270
After Checking Resources
Identify those potential failures that can be
eliminated through commissioning.
n  This is likely to be many.
n  For the remaining, consider QC and QA.
n  All fault tree branches eventually need to be
covered somewhere before the far left box.
n  Let’s consider some examples.
n
Patient
misidentified
Human error:
Omission – Timeout not performed
Or
Training – patient
identified
incorrectly
US images
inadequate
Or
Human Failure:
Inattention/Poor
performance Temp/ate not
seated properly
US probe
misaligned
Incorrect dose,
dose
distribution,
location
Human Failure:
Inattention/Poor
performance Probe cover not
correctly filled
US images
inadequate – QA
failure
Or
RO fails to match
the volume study
images
Fault Tree for
Prostate
Implants with
Loaded
Needles
Training – Probe
cover not correctly
filled
Or
Or
Human Failure:
Poor performance
Changes in
prostate
Training failure
RO fails to align
images along the
range
Or
Human Failure:
Inattention/Poor
performance
US images
inadequate – QA
failure
RO fails to image
adequately
Or
Training failure:
US images
inadequate –
Needle order
Human failure: US
images inadequate
– Needle order
Human Failure:
Inattention/Poor
performance
MP fails to hand
the correct needle
to RO
Or
Confusion between
packages
Poor demarcation
of needles
Poor room layout
MP drops needle
Or
Human failure: MP
slips
Human Failure:
Inattention
RO fails to insert
into correct hole
RO fails to insert
needle properly
Or
Bad viewing
conditions
Confusion
between holes
Or
Training Failure
Sources placed in
wrong location
RO fails to insert
needle to correct
depth
Or
RO fails to hold
stylet stable during
retraction
Or
US images
inadequate – QA
failure
Human failure: RO
fails to hold stylet
Or
Confusion
between planes
Human failure: RO
pushes on stylet
RO selects next
needle that
obscures
subsequent
needles
RO erroneously
modifies source
distribution
Human Failure:
Inattention/Poor
performance
Training Failure
Or
Human Failure:
Inattention/Poor
performance
RO adds
unnecessary
sources
Or
RO fails to add
necessary
additional sources
Or
US images
inadequate – QA
failure
Training Failure
Or
US images
inadequate – QA
failure
Training Failure
Don’t worry
about reading
it, this is for
scale.
One Example
Patient
Misidentified
Human error:
Omission - Time
out not performed
Or
Training - patient
identified
incorrectly
Systemic
corrections
One Example
Quality assurance
Quality control
Managerial
changes
Human error:
Omission – Timeout not performed
Procedural
changes
AND
Patient
misidentified
Or
Training – patient
identified
incorrectly
QC failure: Time
out form
Another Example
Human failure:
Inattention/Poor
performance
MP fails to hand
correct needle to
RO
Confusion
between
packages
Or
Poor demarcation
of needles
Poor room layout
MP drops needle
Or
Human failure:
MP slips
Systemic
corrections
Another Example
Quality assurance
Quality control
AND
Managerial
changes
Procedural
changes
MP fails to hand
the correct needle
to RO
Or
Human Failure:
Inattention/Poor
performance
Failure of call and
response
Confusion between
packages
Poor demarcation
of needles
Poor room layout
MP drops needle
Or
Human failure: MP
slips
Another Example
Training Failure
RO fails to align
images along the
range
Or
Human Failure:
Inattention/Poor
performance
US images
inadequate
Systemic
corrections
Quality assurance
Another Example
Quality control
Managerial
changes
Procedural
changes
Or
Human Failure:
Inattention/Poor
performance
AND
RO fails to align
images along the
range
Training failure
US images
inadequate
US QA failure
Some Thoughts on Human Errors
You can never eliminate human error except by
eliminating the humans.
n  You need to design the system to be resilient to
human error. There are ways to address some
factors that increase the likelihood of human error.
n  Protect it downstream with interventions.
n  Best if these are automatic.
n
Or
Training failure
QC failure:
Prostate image
time out
RO fails to align
images along the
range
Add some QC
down stream
Or
Human Failure:
Inattention/Poor
performance
AND
AND
No Preventing Human Error
US images
inadequate
US QA failure
A Note on Equipment Failure
Equipment failure is not entirely under your
control because sometimes equipment just fails.
You cannot eliminate that possibility.
n  You can do things to influence equipment failure:
n
n  Thorough
commissioning
n  PMI, a resource and procedural issue
n  QA
Ranking of QM Tools
The strength of actions varies:
1. Forcing functions and constraints
2. Automation and computerization
3. Protocols and standard order forms
4. Independent check systems and other redundancies
5. Rules and policies
6.  Education and Information
From the Institute for Safe Medical Practices toolbox
(ISMP, 1999)
Summary
To prevent the effect of a failure requires either
preventing the progenitor cause OR interrupting the
propagation.
n  First, look at redesign and reassess.
n  Ensure resources, environment and key core
components.
n  Commission well.
n  Organize the QM steps by QC and QA.
n  Often it is most efficient and effective to consider
complete branches of the fault tree and process tree
at the same time.
n