8/9/2019 Finding Root Cause
1/51
Finding the Root CauseIdentifying the Context for
Root Cause Investigation
ASQ PALMETTO SECTION
MAY 13, 2008
8/9/2019 Finding Root Cause
2/51
The Journey Ends (almost). . . Review of previous presentations on
addressing audit nonconformance's
Refresher of CREI problem statement
format Every problem originates in a process
Containment and Interim Actions
Root Cause Analysis
8/9/2019 Finding Root Cause
3/51
In Previous Episodes. . .
The preparation shop makes four types ofWidget blanks for the assembly shop,named Type A, B, C and D
Blanks are plastic tubes of variousdiameters made on two extruders
They are temporarily stored in plastic bins
After storage they are transported tocutting machines where they are cut todifferent lengths
8/9/2019 Finding Root Cause
4/51
In Previous Episodes. . .
The assembly shop puts the plastic tubestogether with other products to make a
final assembly They are sold to the automobile industry,specifically Ford and GM
The Widgets must be at the correct length(+/- 2mm) and be free of cracks
8/9/2019 Finding Root Cause
5/51
CREI Problem Statement
A valid problem statement includes: Concern: what is wrong; statement of
nonconformity
Requirement: what should be;documented requirement or reference to
Evidence: data demonstrating thatsomething is wrong; objective evidence
observed that supports statement ofnonconformity
(Impact): how significant is the problemfrom a performance and/or cost standpoint
8/9/2019 Finding Root Cause
6/51
Getting to the Process of Origin
Where was the problem found?
Where is the first process the problemcondition could occur?
Go to these and any processes in betweento collect data recognizing where theproblem is actually first observed; this is
the process of origin! Use a process flow diagram to make this
investigation visual.
8/9/2019 Finding Root Cause
7/51
Step 3A: Containment supportidentification of Process of Origin
Purpose: to isolate theeffects of the problem fromdownstream processes andcustomers; also a source ofdata collection forunderstanding with depthand breadth of the problemand identifying Process ofOrigin
Methods:
Planning of containment Quarantine of product
Evaluation
Data collection
Inputs: CREI statement
Process flow
Timeline
Data to collect for Is/Is NotAnalysis
Outputs: Data re: scope of problem,
(e.g. how many parts areactually affected)
Data for completion of Is/IsNot Analysis
Other opportunities
8/9/2019 Finding Root Cause
8/51
Identify all(potentially)
affected product
Determine howproblem conditionwill be identified
Establishevaluation/
measurementcriteria
Define process forperforming
containment
Determine whatdata to collect from
containment
Test effectivenessof containment
plan
Train personnelperforming
containment action
Performcontainment action
Collect results of
containment foruse in root cause
analysis
4/8/2007Disciplined
Problem Solving
Containment
8/9/2019 Finding Root Cause
9/51
A Root Cause is. . .
A process factorwhich directly definesthe reason for the problem when it ispresent and is having an influence on
the process and its output.
8/9/2019 Finding Root Cause
10/51
Root Cause Analysis Systematic investigation
of a process to identifythe root cause of thegap, and take correctiveaction to eliminate thegap and keep it fromoccurring again in thefuture
The Process of Origin
must be identified,(using data), beforeRoot Cause Analysiscan proceed!
8/9/2019 Finding Root Cause
11/51
Process Hierarchy
System Processes = Policies, Objectives & Practices(how an organization does business)
Audit findings are typically identified at Plan & System level
Planning Processes apply Systemto fulfill customer requirements
Producing Processes to accomplish Plans
Products/Services = output of producing Processes
8/9/2019 Finding Root Cause
12/51
4 Levels of Root Cause
System Root Cause = management systempolicy/practice contributing to Actual Root Cause
Actual Root Cause = previous process factorscontributing to Process Root Cause, (planning)
Direct Process Cause = at Process of Origin
Defect/Detection Cause = Product level
8/9/2019 Finding Root Cause
13/51
Dig! How Deep?
Management decideson depth of root
cause investigationthrough theestablishment ofSMART goals for
each problem solvingeffort.
8/9/2019 Finding Root Cause
14/51
Problem Solving Goals
Define problemsboundaries/depth ofsolutions
Identify right people tosolve problem
Establish measures ofend results
Develop plan of how toaccomplish the goal
Tie problem solvinggoals to organizationalobjectives/targets
Provided to team byManagement
Effective Problem Solvingis based on
SMART Goals:
Specific Measurable Agreed upon by team as
attainable Relevant to organization
and results-oriented Timing defined
8/9/2019 Finding Root Cause
15/51
Root Cause Analysis LevelsLevel(Deep)
Root Cause Consideration Tools Other
(Wide)
Product Defect/Detectioncause
Condition ofcontrols to
detect problem
ControlBarrier
Analysis
What otherproducts havesimilarcontrols?
Process Direct processcause, (trigger atprocess of origin
Factors atprocess of
origin triggeringproblem, (5Ms)
Fishbone,(cause &
effect)
Whatprocesseshave similartrigger cause?
PlanActual root cause,
(led to triggercause)
Linkage toplanning
processes thattrigger cause
5 Why withHypothesis
testing
What otherprocessesaffected?
System weakness inmgt. policies or
practices
Linkage of mgt.system to
actual cause
SystemCause
Analysis
Other affectedmgt. policies
8/9/2019 Finding Root Cause
16/51
Failure Modes & Effects Analysis(FMEA) Clues for Root Cause Investigation
Process
Function
Requirements
Potential
Failure
Modes
Potential
Failure
Effects
Potential
Failure
Causes
Current
Product &
Process
Controls
Process oforigin
Technicaldefinition of
problem
Symptom Processfactors = root
causes
Interimactions
8/9/2019 Finding Root Cause
17/51
Step 3B: Interim ActionIdentifying Product-level Root Cause
(Defect Detection Cause) Purpose: to understand why
the problem condition escapedthe process/organization;evaluation of existing processcontrols forweaknesses/deficiencies;addressing this cause does notprevent recurrence of theproblem
Methods: Control barrier analysis Planning of interim actions
Inputs: CREI statement
Process flow
FMEA
Control plan Outputs: Defect, (detection), cause,
(why problem escapedexisting controls)
Interim controls
Data for Is/Is Not Analysis Methods for monitoring interim
controls to collect data forproblem solving effort
Other opportunities
8/9/2019 Finding Root Cause
18/51
Control Barrier Analysis
(Defect/Detection Root Cause) How did the problemescape the processand/or organization?
Was the problem
anticipated inadvance?, (FMEA)
Were controls definedto recognize andcontain the problem?,(control plan)
At which process arethe planned controlsapplied?, (process flow,control plan)
Were the plannedcontrols in place?
Were the planned
controls working? What is the capability
of these controls? Assists in identifying
appropriate interimactions as well asidentifying thedefect/detection rootcause
8/9/2019 Finding Root Cause
19/51
Process Condition Control Status Capability Observations Actions
Other Opportunities:
Control Barrier AnalysisWorksheet
8/9/2019 Finding Root Cause
20/51
Results of Control Barrier Analysis
May recognize missing controls or controls not workingas planned
Interim actions represent solutions to addressing theseconcerns but should not be accepted as thepermanent solution
When the results of this analysis uncover additionalproblems, refer these to the team champion fordirection on addressing, (Other Opportunities)
Teams main focus at this point is to implement sometype of control to protect downstream processes fromcontinuing to experience the problem
Solutions based on this level of root causeinvestigation mainly are reactive in nature; they onlyimprove our ability to detect the problem condition butdont typically do anything about addressing the rootcause!
8/9/2019 Finding Root Cause
21/51
4/8/2007Disciplined
Problem Solving
Interim ActionDetermine needfor interim action
Identify processfrom whichproblem isoriginating
Can interimcontrol be
added to thisprocess?
Identifysubsequent
process whereinterim control can
be added
Plan type ofinterim control,
(extra inspection,etc.)
Establish accept/reject criteria
Define interimcontrol method
including collectionof results and
identification ofproduct
Prepare temporaryprocess deviationor update control
plan
Train processpersonnel re :interim control
Test effectivenessof interim control
Implement/performinterim control
Collect results of
interim control forroot causeanalysis
Remove interimcontrol when
permanent correctiveaction has been
verified as effectivelyimplemented
No
Yes
8/9/2019 Finding Root Cause
22/51
Note on Interim Actions Management may chose to
accept the Interim Action as thesolution at this point whenOperational Definition is knowndue to scope/impact of problemand priority of other problems tobe solved
Keep in mind that InterimActions do not improve theprocess nor do they solve theproblem
Interim actions are mainly astop-gap
Some interim actions may be
chosen as the solution toaddress the root cause, (one ofthe 3 possible solutions)
Interim actions should not beconsidered permanent until rootcause analysis and solutionselection confirms their validity.
8/9/2019 Finding Root Cause
23/51
Process Cause vs. System CauseProcess Cause What factor of the
process of origin is
triggering the undesirableoutput
What other processesand their factors arecausing the trigger?
Relates product output,(symptom), to processparameters, (causes)
System Cause
Addresses how themanagement system
allowed the process tobecome out of control
Relates process factorcauses to weaknessesin management systems
policies/practices
8/9/2019 Finding Root Cause
24/51
4/8/2007Disciplined Problem
Solving
Process
Root Cause Analysis Identify processfrom which
problem originated
Review data fromoperationaldefinition,
containment and
interim action
Identify potentialcauses
contributing to theproblem
Develop plan totest if potentialcause actually
leads to problem
Conduct test andcollect data
Analyze data fromtest
Does potentialcause directly
lead to problemcondition?
Select otherpotential causes
Can cause becontrolled oreliminated?
Identify possibleactions to monitor
process forproblem condition
Identify possible
actions for eithercontrolling or
eliminating cause
No
Yes
No
Yes
8/9/2019 Finding Root Cause
25/51
Identifymanagement
policies related toprocess from
which problemoriginated4/8/2007
Disciplined ProblemSolving
System
Root Cause Analysis
Review existingpolicies for existing
controls
Do current policiesdefine controls to
prevent the cause ofthe problem?
Identify possiblemanagement
policy controls toaddress cause
Investigate if thesecontrols are in
place
Identify other
processes affectedby these policies
Controlsworking?
Identify how thesecontrols and/orpolicies can be
changed
Analyze whycontrols are notworking at theprocess where
problem originated
No
Yes
No
Yes
8/9/2019 Finding Root Cause
26/51
Direct Process Cause(Trigger Cause at Process of Origin) Must confirm process of origin in order to conduct
investigation of process-level root cause!
Relates one or more factors of the affectedprocess, (process of origin), not behaving as
required to obtain the desired output result at thatprocess
Use Cause & Effect diagram, (fishbone technique)
Direct process causes, (trigger causes), are the
starting point for identifying actual root cause Some action may be required to address the direct
process/trigger cause but actions should not betaken until actual root cause is known
8/9/2019 Finding Root Cause
27/51
Cause & Effect Diagram
Apply to problemsprocess of origin
Gap is head of fish Major cause categories
5Ms Potential causesbrainstormed areprocess factors existingat the problemsprocess of origin
Define potential causesspecifically
When confirmed, thesewill be known as directprocess/trigger causes
8/9/2019 Finding Root Cause
28/51
Fishbone Diagram
8/9/2019 Finding Root Cause
29/51
Fishbone Process
Involve personnel from process of origin inbrainstorming of potential causes at the process oforigin triggering the problem
Develop a sketch/list of the process factors, (man,material, machines, methods, mother nature), related
to the process of origin After brainstorming, review each identified cause toestablish: If the cause is actually a factor at the process of origin If the cause makes sense based on the operational definition
of the problem
Prioritize remaining causes as to their possiblecontribution to the problem condition
Develop hypothesis test to evaluate each potentialcause at the process of origin
8/9/2019 Finding Root Cause
30/51
P i l l
?
i l
i li i i ?
P i i
ii i
l i i
Confi o investi tevi 5 W nal sis:
Di ect P ocess RootCause
Investi ation Plan & ResultsProcess of Origin:
8/9/2019 Finding Root Cause
31/51
Problem Understanding Tools(especially useful in identifying system causes)
Task Analysis reviews process in detail;helpful for operator dependent process
Change Analysis identifies differences;extension of Is/Is Not analysis; expands onapplication of timeline
Both these tools must be applied with alocation context, (process of origin)
8/9/2019 Finding Root Cause
32/51
St t t Q t
Task Analysis Worksheet
8/9/2019 Finding Root Cause
33/51
Change Fact r Diff erence/Change Effect Q esti ns t Answer
What (conditions,
acti ity, equipment)
When (occurrence,
status, schedule)
Where (physicallocation,
environmental
conditions, steps of
procedure)
How (workpractice,
omission, extraneous
action, out of
sequence, poorprocedure)
Who (personnel
involved, supervision)
Change Analysis Worksheet
8/9/2019 Finding Root Cause
34/51
Actual Root Cause Explains why trigger cause/condition exists at the
process of origin
Typically found in previous planning processes
Use 5 Why Analysis with Hypothesis testing to identifyand confirm, (collect data!)
Many problems have multiple causes Usually only one over-riding cause that when addressed,
can significantly reduce the problems impact on theorganization
Very complex problems may have interacting causes but
these are typically viewed as isolated problems that onlyrepeat infrequently, (often managed as Just Do It), untilresources allow necessary time to discover interactionthrough data collection, analysis and experimentation
8/9/2019 Finding Root Cause
35/51
5 Why Analysis
Ask Why does thishappen? for each identifiedprocess cause from Cause &Effect diagram
Differentiates betweenprocess, (direct) cause and
underlying root cause Each level of causes
identified in 5 Why analysismust also be confirmed viatesting in order to verify rootcause
Deeper levels of 5 WhyAnalysis which get intoPlanning processes willrequire interview-type datacollection
8/9/2019 Finding Root Cause
36/51
5 Why Analysis Worksheet
Processof Origin
Cause
Plan/Datato confirm
Results 2ndlevel
Cause
Plan/Datato confirm
Results 3rdlevel
Cause
Plan/Datato confirm
Results 4thlevel
Cause
Plan/datato confirm
8/9/2019 Finding Root Cause
37/51
Test Potential Root Causes
Validating causeguesses bycollecting and
analyzing data Test under controlledconditions
Turn the problem on
and off bymanipulating thesuspected cause
8/9/2019 Finding Root Cause
38/51
Hypothesis Testing
Design hypothesis and select methods for testinghypothesis - state how potential cause could resultin described problem; decide what data to collect thatwould prove potential cause; establish acceptablerisk of decision outcome; determine sample size;develop action plan for study
Prepare to test hypothesis - organize and preparematerials required to conduct study; collect dataduring study
Analyze results of test - analyze data usingappropriate statistical tools, (t, F, Chi-squared tests)
Interpret results - conclusions from study; does dataestablish potential cause as reason for problem?
8/9/2019 Finding Root Cause
39/51
Root Cause Analysis Plan
Identify causes to be investigated
What data supports each cause?
Can cause be introduced and removed to
confirm presence/absence of problem? What tests will be performed to confirm rootcause?
What is the statistical confidence of these
tests? (i.e. how much data is needed?) Results of tests recorded and analyzed withconclusions drawn
8/9/2019 Finding Root Cause
40/51
System Causes
What in the system allowed this problem/causeto occur
Identifies why the process root causes occurredbased on current management policies/practices
Often not readily measurable
Data obtained through interview
By identifying system causes, systemicimprovement can be made in order to preventrecurrence of problem in other similar processes
Typically addressed once process root causes ofproblem are known and confirmed
S stem Ca se Anal sis Worksheet
8/9/2019 Finding Root Cause
41/51
System Cause Analysis Worksheet
Operational Definition:
Process of origin cause:
Process root cause:
Which management system process is the process root cause relatedto
Who is responsible for this management system process
What documentation/policies are available describing actions andcontrols for this management system process
Does this documentation/policy recognize the possibility for thisproblem to occur
Are there any current management system controls in place to
prevent or detect this problem
Has this management system process been associated with previousproblems
What other processes within the organization are driven by thismanagement system process
Possible Management System Level Solutions: 1) Create new policy2) Change existing policy 3) Reinforce/re-apply current policy
8/9/2019 Finding Root Cause
42/51
As a result of Root Cause Analysis
Product-level cause, (related to current controls),identified and confirmed along with appropriateinterim controls to protect downstreamprocesses/customers
Trigger cause at process of origin identified andconfirmed
Actual root cause, (what allowed the triggercause to exist at the process of origin), known
and confirmed System root cause identified, relating actual rootcause to management policies/practices
8/9/2019 Finding Root Cause
43/51
A Key Outcome of Every ProblemSolving/Root Cause Investigation. . .
Expansion of Knowledge
8/9/2019 Finding Root Cause
44/51
Next Steps, (Next Year?)
Solution identification, (3 possiblesolutions to every problem), andevaluation/selection for each root causelevel
Implementation of selected solutions
Verification of the effectiveness of
implemented solutions
Lessons learned
8/9/2019 Finding Root Cause
45/51
Other Opportunities
Identified typically while collecting data for Is/Is NotAnalysis, Root Cause investigation/confirmation, solutionevaluation
Record these other problems/opportunities
Share these problems/opportunities with team championto get direction on how to address: (change scope ofcurrent problem solving effort to include; managementassigns another team to address)
Dont allow these other opportunities to distract from thefocus of the problem solving effort
These Other Opportunities become the Bonus of aneffective problem solving effort
8/9/2019 Finding Root Cause
46/51
Your Turn for Root Cause Analysis
For previous case study on widgetmanufacture:
CREI statement, (given)
Process flow, (given)
Is/Is Not analysis, (given; process of originknown)
Fishbone potential causes at process of origin Create questions for 5 Why investigation
8/9/2019 Finding Root Cause
47/51
Widget CREI
Concern: customer complaint from GMre: cracked tubes, (widgets)
Requirement: per GM drawing #123,assembly should be free from cracks
Evidence: GM customer complaint
Impact: assembly leaks, (performance),GM is requiring contained shipping, ($$$)
8/9/2019 Finding Root Cause
48/51
Widget Making Process Flow
8/9/2019 Finding Root Cause
49/51
Is/Is Not AnalysisFocus Aspect Data to
Collect
Where to
Collect
How to
Collect
Results
IS
Results
IS NOT
Comments
What? Problem
condition
# cracked
tubes
Process
flow
Visual
evaluation
Visible
cracks ontubes
Other
defects
Refer to
requirement
Where? Geographically
Processes wherecrackedtubesfound
Processflow
Noteprocesseswherecrackedtubes found
Cutting,customer
Extrusion,assembly,finalinspection
See processflow
Where? On output Locationon part
Duringcontainment
Concentration diagram
Cracks atedge oftube
Cracksalonglength orin otherlocations
Refer toproblemcondition
When? First seen Problemreport
Customerservice
Review ofcustomer
complaints
4/28/08,(date of
customercomplaint)
Prior tothis date
Refer totimeline
Who? Identifiedproblem
Names,positions,contactinfo
Customerservice
Interview GM,(customer)
Othercustomers
Involved inrelated
Functions Processflow
Interview Cuttingoperator
Othercutting
Refer toprocess flow
8/9/2019 Finding Root Cause
50/51
Fishbone Diagram
8/9/2019 Finding Root Cause
51/51
Possible Questions for5 Why Analysis
Top Related