CTQ/VOC Critical to Quality In the Voice of the Customer

The CTQ process helps us to put metrics to quality ¡ CTQ is a tool that helps us find a way to measure

process ¡  Defect ¡  Unit ¡  Opportunity

¡  This is not an easy thing to do

Start With The Customer

¡ Gather comments in the Voice of the Customer ¡  Customer Needs ¡  eSurveys ¡  Focus Groups ¡  Surveys ¡  emails ¡  Comment cards

¡  Translate them into issues and specifications

¡ CTQ (Critical To Quality) – a product or service characteristic that must be met to satisfy a customer specification or requirement.

Then we define our defects

¡ A defect is defined as any part of a product or service that: ¡  does not meet customer specifications or

requirements, or ¡  causes customer dissatisfaction, or ¡  does not fulfill the functional or physical

requirements.

We define our units

¡ A unit is something that can be quantified by a customer

We define our opportunities ¡ Opportunities are the total number of chances

per unit to have a defect ¡  Each opportunity must be ¡  independent of other opportunities ¡  measurable ¡  observable ¡  it directly relates to the customer CTQ

¡  The total count of opportunities indicates the complexity of a product or service

Let's look at some examples ¡ Our aims is a number ¡ A quantifiable measure of quality ¡  Usually errors per something ¡  Example: ¡  Survey completions/survey starts = measure of

usability ¡  Want to answer 85% of calls within 20 seconds

Call Center ¡  Customer Quote: 'I consistently wait too long to speak to a

representative.' ¡  CTQ Name: Representative Responsiveness ¡  CTQ Measure: Time on hold (seconds) ¡  CTQ Specification: Less than 60 seconds from call connection to

the automated response system ¡  Defect: Calls with hold time equal and greater than 60 seconds ¡  Unit: Call ¡  Opportunity: 1 per call ¡  Calculate Your Sigma

¡  Defects: 263 calls ¡  Units: 21,501 calls ¡  Opportunities: 1 per call ¡  Sigma: 3.75

Book Publisher ¡ Customer Quote: 'I can't stand typos in books I purchase.' ¡ CTQ Name: Typographic Quality ¡ CTQ Measure: Number of typographical mistakes ¡ CTQ Specification: Zero typographical mistakes ¡ Defect: Any typographical mistakes ¡  Unit: A word ¡ Opportunity: Words per book ¡ Calculate Your Sigma ¡  Defects: 2 typographical mistakes ¡  Units: 100,000 (500 words/page x 200 pages/book) ¡  Opportunities: 1 per word ¡  Sigma: 5.61

Printed Circuit Board Manufacturing ¡ Customer Quote: 'Boards must work when I plug them in.' ¡ CTQ Name: Board Functionality ¡ CTQ Measure: Non-functioning or improperly functioning

boards ¡ CTQ Specification: All boards function properly ¡ Defect: Any non-functioning or improperly functioning board ¡  Unit: A board ¡ Opportunity: Total number of parts plus solder points ¡ Calculate Your Sigma ¡  Defects: 18 boards ¡  Units: 1,000 boards ¡  Opportunities: 58 (1 board + 13 resistors + 4 capacitors + 2 diodes +

38 solder points) ¡  Sigma: 4.92

Conclusion ¡  To measure quality you can use CTQ/VOC ¡  First gather customer quotes ¡  Translate them into quality points ¡  Figure out how to measure them ¡ Determine defects, units, and opportunities ¡  Set an acceptable range