finding root cause

Upload: hardycheitb

Post on 29-May-2018

239 views

Category:

Documents


0 download

TRANSCRIPT

  • 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