The Quality Improvement Model

1. TheQualityImprovementModel Define Process Select Measures Collect & Interpret Data Collect & Interpret Data: Diagnosing Variability IsProcessStable? No Investigate & Fix Special Causes Purpose: Begin to understand why there is variability in data collected Yes IsProcessCapable? No Improve Process Capability Yes Use SPC to Maintain Current Process

2. 1 2 3 4 5 6 7 8 9 10 11 12 What size shoe do you wear? Size 11 Shoes Why aren’t size 11’s all the same size?

3. GC CHDM Test Method Example Why don’t we get the same %Water value?

4. Cause & Effect Matrix – A Tool to Identify and Quantify Sources of Variation Cause & Effects Matrix

5. Cause and Effects Matrix • Relates the key inputs to the key outputs (customer requirements) using the process map as the primary information source • Key outputs are scored as to importance to the customer • Key inputs are scored as to relationship to key outputs • Pareto of key inputs to evaluate in the FMEA and control plans • Input into the initial evaluation of the Process Control Plan

6. Cause & Effect Matrix Steps • Identify key customer requirements (outputs) from process map or other sources • Rank order and assign priority factor to each Output (usually on a 1 to 10 scale) • Identify all process steps and materials (inputs) from the Process Map • Evaluate correlation of each input to each output • low score: changes in the input variable (amount, quality, etc.) have small effect on output variable • high score: changes in the input variable can greatly affect the output variable • Cross multiply correlation values with priority factors and sum for each input

7. Examples Note: Only a partial list

8. Bottle Production Example Note: Only a partial Map

9. Cause & Effect Matrix Form 1. List Key Outputs Excel Template C&E Matrix.XLS

10. Bottle Production Example 1. List Key Outputs The Outputs are defined in Step 1 of Process Mapping

11. Cause & Effect Matrix Form 2. Rank Outputs as to Customer importance

12. Bottle Production Example 2. Rank Outputs as to Customer importance

13. Cause & Effect Matrix Form 3. List Key Inputs by Process Step Note: Information obtained from process map

14. Bottle Production Example 3. List Key Inputs by Process Step This step uses the Process Map inputs directly. Notice the Process Inputs follow the Process map step-by-step. Note: Only a partial list of inputs

15. Cause & Effect Matrix Form 4. Relate Inputs to Outputs

16. Relating Inputs to Customer Requirements • You are ready to relate the customer requirements to the process input variables • Correlational scores: No more than 4 levels • 0, 1, 3 and 9 • Assignment of the scoring takes the most time • To avoid this, spell out the criteria for each score: 0= No correlation 1= The process input only remotely affects the customer requirement 3 = The process input has a moderate effect on the customer requirement 9 = The process input has a direct and strong effect on the customer requirement

17. Bottle Production Example 4. Relate Inputs to Outputs Note: Only a partial list of inputs This is a subjective estimate of how influential the key inputs are on the key outputs

18. Cause & Effect Matrix Form 5. Cross-multiply and prioritize Sum of (Rating x Correlation Score) values for all Requirements

19. Bottle Production Example 5. Cross-multiply and prioritize Note: Only a partial list of inputs We now start getting a feel for which variables are most important to explaining variation in the outputs

20. Bottle Production Example We have sorted on the cross-multiplied numbers and find that the input variables in the box above are the most important We can now evaluate the control plans for these input variables Note: Only a partial list of inputs

21. General Approach • Place the outputs across the top of the matrix and rank • Place inputs down the side of the matrix starting with the first process step and moving to the last • This approach is okay for small process with relatively few steps • Should only be used for processes with a relatively small number of steps and inputs

22. Focused Approach • Phase I • Place the outputs across the top of the matrix and rank • Place the process steps down the side of the matrix • Correlate process step to outputs • Pareto the process steps • Phase II • Start a new C&E Matrix with the inputs from the top three or four process steps • Recommended when first starting a project • Focuses the efforts and gives the team a feeling that they’re working on the important process steps first • Gives you a running start at the FMEA and preliminary Control Plan Analysis

23. Control Plan Evaluation • Standard Operating Procedures • Do they exist? • Are they understood? • Are they being followed? • Are they current? • Is operator certification performed? • Is there a process audit schedule?

24. Control Plan Evaluation • Controllable Input Variables: • How are they monitored? • How often are they verified? • Are optimum target values and specifications known? • How much variation is there around the target value? • How consistent are they? • Other Questions: • How often is the input variable out of control? • Which input variables should have control charts?