A fishbone diagram, also known by its technical term 'cause-and-effect diagram' or 'Ishikawa diagram', is a visual tool used to organize potential causes of a specific event. It's a highly effective problem-solving technique used to identify potential causes of a problem, before choosing which ones should be investigated in further detail.
This simple yet powerful tool gets its name from its visual resemblance to the fish skeleton. The event that needs to be analyzed is placed at the head of the fish, and the causes branch out like the bones of a fish.
The History and Origin of Fishbone Diagrams
Fishbone diagrams were popularized by the distinguished Japanese quality control pioneer, Dr. Kaoru Ishikawa, in the 1960s. Ishikawa is also credited with creating the Quality Circles concept, which led him to develop this problem-solving tool.
Although originally used in the manufacturing and engineering sectors, fishbone diagrams have since been widely adopted across various industries, including healthcare, software development, and customer service, due to their versatility and simplicity.
The Fish's Head: The Event
The event or issue that needs to be addressed is always placed at the top of the fish to ensure the problem is clearly defined and stays the focus of analysis. This can be a specific problem, the effect you want to achieve, or a goal you want to reach.
For example, if a company is experiencing a high customer complaint rate, the event could be phrased as: "High number of customer complaints".
The Bones: The Causes
The bones of the fish represent the potential causes which can be categorized into several groups. These can be defined as: People, Methods, Materials, Measurements, Machines, Mother Nature (environment), and Management.
Each cause is considered a "bone" in the fish diagram. They can be further broken down into even smaller categories, like merchandise, package, pricing, etc. Each category is a different "bone".
Creating a Fishbone Diagram
Here's a step-by-step guide to help you create a fishbone diagram to tackle problems effectively:
1. Clearly define the event or problem that you want to analyze at the head of the fish. Make sure everyone involved understands the event.
Brainstorming the Causes
2. Identify and categorize potential causes for the event. Start writing them down on sticky notes, which can later be organized into categories and rearranged as needed.
3. Organize the causes into the six categories (People, Methods, Materials, Measurements, Machines, and Mother Nature/Environment).
Refining and Connecting Causes
4. Once you have a list of all plausible causes, start arranging them into the fishbone diagram template. Group related causes together and start refining the levels of detail as needed.
5. Connect related causes and use sub-diagrams to represented deep levels of detail.
Analyzing the Diagram
6. Once the diagram is complete, it's time to analyze it. Start at the head of the fish and work your way down, assessing the likelihood and impact of each cause.
7. Based on your analysis, prioritize the causes and determine which ones should be investigated deeper.