The SIPOC (suppliers, inputs, process, outputs, customers) process map is one of the most valuable tools in a Six Sigma professional’s toolbox. It typically can be completed with the project team in less than an hour, and has a strong tie to the project charter. It also makes previously unknown customers suddenly appear out of thin air. The SIPOC provides an end-to-end picture of a process and is the linchpin of the Define phase of any DMAIC (Define, Measure, Analyze, Improve, Control) project.
But why not rearrange the letters and call it POCIS? Starting with the process can be the most effective and efficient way to complete this tool because of its tangible characteristics –– it is easy to visualize the process. Once the high-level process steps are defined, it is possible to determine the outputs and customers. The tool is then complete after identifying the Inputs and Suppliers (hence,– POCIS).
Completing the POCIS
Before beginning the POCIS, practitioners should ensure that the right group of people has been gathered. Remember, the quality of the POCIS is a reflection of the strength of the team assembled.
The first step is to list the process steps, remembering to keep the detail at a minimum by only outlining five to eight steps. When describing the process steps, try to limit the description to two words. Have each description start with a verb (action) and end with a noun (subject).
The next piece of the POCIS to fill in are the outputs. Here, the team wants to understand the final product or service of the process. By understanding the outputs, it is possible to identify the true customers. The customers are defined as those individuals who consume the product or service created by the process. Now that the process, outputs and customers are known, it is time to identify the inputs. Inputs are the triggers, raw materials and equipment needed to complete the process. Finally, the team should list the suppliers of those inputs.
That’s it – the POCIS is complete. Next, the magic begins.
Ab-Ra-Ca-Dab-Ra: Revealing Meaning
After the POCIS diagram is in place, practitioners can begin interpreting and analyzing the usability of the information documented for each component:
Process – Here practitioners learn valuable information for scoping the project. This information ties directly back to the charter, and it can be used to help identify the start and stop point of the process, as well as what is considered in and out of scope. The process also can be used to help pinpoint redundant steps, rework, loops, hidden factories and non-value-added steps. This will help focus the data collection plan during the Measure phase.
Outputs – This is the first look at the project’s Y (output) metrics. The information gathered here can be used as a verification of the voice-of-the-business goals documented in the charter. The outputs also can work as a starting point of discussion with the customers.
Customers – This section is a valuable starting point for the voice-of-the-customer (VOC) step in DMAIC. It helps to identify who should be involved when gathering critical-to-quality (CTQ) metrics. If the VOC analysis was completed prior to the POCIS, the POCIS serves as a verification tool that no customers have been overlooked. Finally, this section is a great place to find potential team members, especially when the Customers of the process are internal associates; these customers should be included in the team whenever possible.
Inputs – Consider this a mini-fishbone diagram because it is the first swipe at the potential causes of the problem. At this point, the diagram is probably too high-level to consider these root causes, but they are definitely must-haves to start the root cause analysis brainstorm session.
Suppliers – Think of these individuals as stakeholders of the improvement. In most cases projects, the root causes are supplied by one of the suppliers listed on the POCIS. The improvements are focused on the root cause and, therefore, on the supplier. This is why the suppliers should be considered as stakeholders and definitely, if possible, members of the team.
Nothing Tricky About It
The POCIS, or SIPOC, is also sometimes referred to as COPIS. Regardless of what it is called, it is a simple and powerful tool that every Six Sigma professional should have in their magic box.