Six Sigma: DMAIC methodology

Define: problem. Business case. Scope. Defect. CTQ: Critical-To-Quality factors (a.k.a KPIs). Risks. Current & to-be process maps. Deliverables.
Focus the issues again on the problem definition to filter out CTQs.
Tools: Project Charter.
To generate CTQs: SIPOC, Fishbone, Process Flow. Process Mapping.
To filter CTQs: QDF. FMEA. Pareto Chart (80-20 rule: 80% of errors can be removed by solving 20% of problems).

Measure: CTQ(Calculated measure)=f(x: Base measure). Deliverables Times. Cost(bad&good quality). Revenue. Progress & success measure & values: KPIs(e.g. ThisPeriod/LastMPeriod>1). Correctness & Completeness of measures & values.

Tools: Measurement System Analysis. Gauge R&R. Process Capability.

Find the root causes:
Qualitative Analysis:
Fishbone (Materials, Men, Machines, Methods, Measures, Environment). Where the head of the fish is the CTQ factor.
5 Whys: Find 5 reasons of the existing of the CTQ factor. Then for each of these repeatedly find their 5 reasons, until you build a tree of reasons of 25 leafs representing the root reasons, if possible.
Focus again on the problem definition to filter out reasons.
Quantitative Analysis:
Correlation and Cause&Effect analysis
 to choose the most influencing reason.

Also analyze: Resources, Risks & difficulties for the change.

1. Generate ideas: Brainstorm. Benchmark to find solutions.
2. select best solution from these ideas: evaluate the effectiveness of such solutions through:
  Qualitative Evaluation:
(For DMADV, new products): Quality Function Deployment.
  FMEA  (For DMAIC, improving existing systems): Failure Mode   Effect Analysis. And:
  Quantitative Evaluation: 
Correlation and Cause&Effect analysis to choose the most influencing measure/solution.

3. Implement: After finding the solution factor that influences the   CTQ(KPIV) the most, produce a plan to maximize/minimize it to optimize the CTQ.
Then Break to tasks/agile Stories and re-Integrate.

Control: quality, cost, risks, changes. By:Training. Surveys. Reviews. Statistical Process Control Chart: Measuring and Plotting the post-improvement status and comparing it to a max and min acceptable variation bars.

Example – Services QTC (KPIs):

• Accuracy

• Cycle time

• Cost

• Customer satisfaction.

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