Process Inputs and Outputs

Before a process can be improved, it must first be measured. This is accomplished by identifying process input variables and process output variables, and documenting their relationships through cause and effect diagrams, SIPOC and other similar tools. Inputs (Xs) are causes which are independent variables which results in specific outputs (Ys) or effects which are dependent variables. Thus, process maps are expanded to cover customer and supplier by SIPOC to gather measurable data from all.

Inputs – It’s important that your team clearly understands the relationship between the inputs, the process, and the outputs. Inside the process you have many X factors that together end up dictating the amount of variability, the quality, and the repeatability of your output Y factor. The variables on the outputs can be many things including, for example, context and response time, the order to delivery time for a custom bicycle, a loan approval cycle, or a visit to the doctor. You need to recognize that outputs for any end-to-end process can in turn become inputs to a subsequent or downstream process later on.

Process Boundaries – Process boundaries and dictating what those are is an important aspect of defining the project and where you are going to focus your efforts. There are transition points between each of the steps. You need to understand where you transition from one functional process to another. For example, with a manufacturing company, you could have process boundaries starting with ordering an aircraft part. And that could begin with the receipt of the order at the company and then we would have the various operations that would occur down to the inspection of that part, pass/fail. And if it’s good, you can ship it to the customer. If it fails, you’d rework it and pass it back through.

SIPOC

SIPOC stands for Suppliers-Inputs-Process-Outputs-Customers and has been discussed earlier. SIPOC addresses issues regarding the input, output, supplier and customers like output being produced by the process, who provide inputs to this process, what are the inputs, what resources does this process use, which steps add value, etc. These issues apply to all processes and SIPOC addresses by putting in place a standard format.

SIPOC development is initiated with persons having knowledge of the process and then conducting a brainstorming session to describe the problems and garner consensus for resolution.

Example – A catalogue retail company call center use this SIPOC diagram to define the scope of the process, including: the start and end of the process, the major steps, the primary inputs and outputs, and the key customers and suppliers. With this simple yet comprehensive picture at hand, every staff or member involved in this activity will have a deep and clear understanding of this process.

As it’s a high-level picture, it won’t include many details. The major steps on process part will be limited to less than 7. Usually a flowchart with arrow connectors showing the sequence can best present the steps. In this example, five steps are used to illustrate the main procedure.

Development of SIPOC involves identifying the process steps then, identifying the outputs of the process followed by the customers receiving the outputs of the process, then the inputs and the supplies of the required inputs.

SIPOC Elements – It’s important to recognize the different factors as you work through the SIPOC diagramming process. These can be captured as a spreadsheet or a flipchart. For many service processes, the customer actually makes a request as an input to your process, so they are in essence a supplier. Then you do a value-add activity, give the customer the output, and they receive it in the end.

Inputs can be raw materials, instructions, data, drawings, specifications, quality requirements, standard operating procedures, labor, resources, machines, and equipment used throughout the entire process. The process itself can take a variety of forms such as a value stream map, a process map, or a swim lane chart. You need to recognize that outputs, or Y values, that you’re trying to accomplish are products of the various actions that take place during the process. The function of the X factors in the process is to give you the quality of the output that you’re looking for at the end of the process.

An output can take many forms, such as a value-add task completion that’s ready for the downstream step, a report, a product, a part, or an assembly. It could be a new specification you’re going to use, a certification that your customer requires, a check to send to the customer, or an approval or a permit that you’re issuing.

The last element is the customer. The customer defines the key features and functions, what is appealing, and the top issues. You use that information to seek out root cause analysis and work upstream to make sure your process is delivering optimal results.