Learn how to use the input-process-output (IPO) model
You might have read that the input-process-output (IPO) model can be helpful in business and other organizations, but you’re not sure precisely what it means and how to apply it. That’s understandable — the phrase might sound like a complex computer system or an intimidating theory.
The reality is that the IPO model is very easy to understand. While it has roots in computer programming, it appears in many different industries and settings because it’s an effective way to plan, analyze, and improve how work gets done.
After reading this post, you’ll understand what the input-process-output model is all about and be ready to apply it to your business processes. You’ll learn:
- What the input-process-output (IPO) model is
- How to use the IPO model
- Benefits of the IPO model
- Examples of input-process-output in different industries
- Best practices when thinking about IPO
What is input-process-output (IPO)?
Input-process-output (IPO) — also called an IPO model or IPO diagram — is a visual tool used to describe a workflow, the flow of information, or activities within a system. An IPO diagram helps you identify all the factors that influence a process and all the process’s outcomes, and it gives you a structured approach to analyzing and improving the system.
The IPO diagram consists of three columns listing inputs on the left, describing the process in the middle, and then tracking the outputs on the right. By diagramming a process in this way, almost any business — including computer science, systems analysis, and business analysis — can better identify the cause of a problem and improve a system’s performance.
As part of Six Sigma methodology, the IPO model fits within a more complex technique called DMAIC — which stands for Define, Measure, Analyze, Improve, and Control. The input-process-output model is an important part of the Define stage of DMAIC because it helps clarify and define a project’s goals, scope, and boundaries. This clarity helps to establish a solid foundation for the subsequent stages.
IPO assumes that if we control causal factors, we can also control their effects. Drawing the workflow using an IPO diagram can help visualize any system where it’s difficult to see how all the pieces connect. Although it’s primarily descriptive, teams can use IPO for analytical, quality control, or planning purposes. It’s useful in production, manufacturing, teamwork, and many other areas.
How to use the IPO model
Creating your own initial IPO model is relatively easy. The IPO diagram gives you a simple framework for listing the inputs and outputs of any system. The details will depend on your industry and the specific process you want to explore.
Getting the details right — and knowing the difference between inputs, process steps, and outputs — can require careful thinking. Let’s examine each category:
- Input can include data, information, or resources that enter the system.
- Process can include activities, transformations, or operations performed on the inputs.
- Output can include results, products, or outcomes produced by the processes.
In manufacturing, a general, high-level IPO diagram might look something like this:
Although this diagram establishes a cause-and-effect pattern from left to right, you don’t necessarily need to start with inputs. If you’re planning a new process, try starting with the desired output and working back. The output should be thorough, specific, and measurable. Output is usually focused on four categories of standards that organizations are trying to achieve — quality, cost, time, and safety.
One drawback of the IPO method is it’s hard to account for random variables. To identify all possible inputs, consider people, environmental factors, methods, measurements, materials, and machines. As you define the process, break it down into clearly defined steps. Once the model is complete, you can analyze the process to determine relationships and identify areas for improvement.
Benefits of the IPO model
There are many benefits to using the IPO model, such as:
- It’s easy to use. You don’t need to know how to use software or have specific expertise and training. Anyone can create an IPO diagram and spend time thinking about factors in a process.
- It’s versatile. It’s used in different industries and can be applied to almost any business process. You don’t have to follow a set of prescribed rules. You can apply this framework creatively, depending on your goals.
- It helps define key process input variables. Use the model to gain insights into how different factors contribute to the overall output and identify how to improve your input.
- It helps streamline operations. Identify bottlenecks, redundancies, or inefficiencies in operations. This understanding allows teams to reconfigure processes, allocate resources effectively, and streamline operations for better performance and productivity.
- It helps with problem-solving. Businesses can analyze the IPO diagram to identify potential causes and effects when an issue or challenge arises. They can pinpoint areas where disruptions may occur, allowing them to troubleshoot and rectify the problem more effectively.
- It can enable training and documentation. The model provides a visual representation of a business process, making it easier to convey information and train new employees. IPO can be a reference tool for documenting and preserving knowledge about processes within an organization.
- It helps clarify process steps and why. It can help eliminate what does not produce a good outcome.
- It’s a good communication tool. The model allows teams or stakeholders to visualize and discuss the flow of information within a system. It facilitates effective communication and collaboration by providing a common understanding of how inputs become outputs. This shared understanding enables teams to work together more efficiently and make informed decisions.
- It’s a good introduction to more complicated Six Sigma process mapping. The SIPOC (Supplier, Input, Process, Output, Customer) diagram adds the supplier to the start of the process chain and the customer to the end of it. This method can extend the IPO diagram beyond internal processes to map out a larger chain of cause and effect. IPO is also a helpful concept to master before exploring value stream mapping.
Examples of input-process-output in different industries
The input-process-output model emerged in the twentieth century as a fundamental model for describing complex computer systems. However, IPO quickly found applications outside of computer programming as a practical methodology in general systems theory and design. Many businesses found that by diagramming processes, they could improve quality and efficiency. IPO diagrams are now used in various industries. Some of the most common are:
- Manufacturing. The IPO model can show the most important factors influencing production outcomes. Companies can then identify bottlenecks, optimize resource allocation, improve quality, and enhance efficiency.
- Commerce. In online order processing, the input happens when a customer places an online order. The process happens when the order is received, the cost is calculated, and payment is processed. The output includes an order confirmation, an inventory check, shipping, and a confirmation email.
- Software development. A software development process could include gathering requirements, designing, coding, testing, and deployment. In software, it’s a good idea to start with output, break down the input variables, and determine the process of code needed to generate a fully functioning application as the output.
You might also encounter the use of IPO diagrams in the social sciences, food and hospitality, economics, finance planning, and other areas. The principles of the model are foundational enough that they can be applied almost anywhere.
Best practices when thinking about IPO
While practices differ depending on the industry, if you are looking to improve the performance of a team or system, there are a few basic principles to follow when applying this model.
To avoid common pitfalls, plan ahead and check that your diagram is:
- Achievable. Define an attainable scope for your processes and make sure your processes are within that scope.
- Comprehensive. Consider all the possible outputs before capturing or changing your inputs. Likewise, check that you have anticipated all possible inputs, both those you add intentionally and others that might be harder to control.
- Inclusive. Make sure to involve the whole team to avoid bias on what should go into the inputs and outputs.
Get started with the input-process-output model
The IPO model is a simple but effective way to think carefully about cause and effect in small and large systems. Whether you want to improve teamwork, discover the cause of a problem, increase revenue, or design a more efficient system, this framework can help you achieve your business goals.
When you’re ready to get started, decide what business process you want to analyze and sketch it out with paper and pen using this method. Then explore Adobe Workfront, which can help you design a workflow using the input-process-output model and identify all the factors in your work processes that lead to success.
Workfront is enterprise work management software that connects work to strategy and drives better collaboration to deliver measurable business outcomes. It integrates people, data, processes, and technology across an organization so you can manage the entire lifecycle of projects from start to finish. By optimizing and centralizing digital projects, cross-functional teams can connect, collaborate, and execute from anywhere to help them do their best work.