Six Sigma is often thought of as a statistic heavy method and to some degree that is true. But the truth about statistics is if you don’t understand what they are trying to tell you, then they are just numbers on a page. The good news is that the purpose of Six Sigma metrics generally fall into 3 categories: can I make it better, can I make it faster or can I make it cheaper.
Basic Metrics Help Me Make It Better
These metrics are typically Defects per Unit (DPU), Defects per Million Opportunities (DPMO) and Rolled Throughput Yield (RTY). The purpose of these metrics is to decide whether you can eliminate waste and increase the quality of your end product. This is a metric that will not create an almost answer, you will identify and work from a root cause perspective.
Basic Metrics Help Me Make it Faster
This measurement deals almost exclusively with cycle time, this category is almost singularly concerned with reducing production and delivery time. Focus on the cycle time requires you to focus on the process from cradle to grave. You are looking very much to reduce variations and eliminate non value added activities.
Basic Metrics Help Me Lower Cost
This metric requires you to deal with the cost of poor quality (COPD). If this is a measurement that you are using, your purpose is to find out where the quality problem is, how much it is costing the organization and how to eliminate it.
This is a basic summation of how you will decide what type of metrics to use, next week we will go into detail about specific metrics. Knowing why you are measuring something and what you need those measurements to tell you is the most important part of your 6Sigma project. Your belt will be able to walk you through a specific measurement and offer advice as to whether or not it is the best metric to use.
DMAIC is a staple of Six Sigma methodology and like all things Six Sigma, the better your understanding of the tool the greater its abilities. So just what is DMAIC? Basically it’s a problem solving tool, what is great about it is that it specifically works with unknowns and teaches your staff how to use a lack of information to their advantage.
What is DMAIC?
Define: This is where you will put in the most work, because at this stage you will be setting the ground work for all of your changes. You will need to define everything here, specifically critical to quality variables and identified process problems.
Measure: Collect information and review data. The catch to this step is to ensure that your measurement systems are substantiated. When using measurements you will need to ensure that they are measuring specific data and that the measured data aligns with your organization’s goals. Not sure how to do this? Have a conversation with your belt and your executive team; they will point you in the right direction.
Analyze: In this step you will be asking your staff to study the relationship between processes and qualify their impact on the quality of your products or services. Ideally you will want knowledgeable staff involved in this process, but how do you start and what do you do? Talk to your belt, they can guide you effectively and easily through this process.
Improve: This is the area that will allow you to humanize 6Sigma from your staff by focusing less on measurements and more on innovation. You should be looking for suggestions and then moving on to a process of elimination. This is an area where I like to implement ‘dry runs’ of the solution to show me where the process improvements are realistic and where they are not.
Control: This is one of the most important parts of the process, but it can only occur once the other steps have been completed. Failure to complete the previous steps guarantees that you will be perfecting the wrong change. In this step, the devil is very much in the details. You must be vigilant and flexible; your belt will help you put together the best control strategy for your organization.
DMAIC is all about making a change work for your organization. You don’t have to produce complicated charts and statistics for it to work for your organization, but you do have to understand how it works. Although this is a simple summary, there is enough information to get started. When you are ready to get down to detail and create a DMAIC strategy, SPC can help.
Happy New Year! As 2012 unfolds I thought we would look at the Critical to Quality Tree and how it works. The Critical to Quality Tree is a tool that helps visually identify what activities are ‘critical’ to success. With all things critical will mean different things to different industries and organizations, but this post will aim at providing you with a road map to begin your quality journal.
What does the Critical to Quality Tree look like?
The good news is that a Critical to Quality Tree is very easy to construct, here’s a sample.
The needs section is where you identify what you know your organization needs to improve upon. There is no formula for this identification except for the goals you have set for yourself and what your customer feedback has identified.
The drivers section is essentially the solutions to the need that your improvement team has identified. This is where brainstorming and innovation can begin to take root. The purpose of this section is to give your team a concrete roadmap that highlights where they should direct their energy.
The CTQ section is quite simply how you will make those changes. The beauty of a CTQ tree is that is forces you to create concrete and actionable strategies. In effect it creates accountability and focus, all your strategies are now able to be centered on your specific goal identified in the needs section.
What it doesn’t do
The Critical to Quality Tree does not provide automatic solutions and it does not measure process quality. If this is a method that you are thinking about, be aware that you will have to provide the information. What is unique about CTQ is that there are no stats involved, before you get happy understand that this does not make it a light activity. You have to be very specific and you have to know your exact market before you start the activity.
As always, this is not a step by step approach but a general introduction to the tool. It can be very useful and produce a tangible tool for your staff to use in creating and implementing solutions.