We explain what an Ishikawa or cause and effect diagram is, its structure and what it is for. Additionally, you will understand how to make one with examples.
What is the Ishikawa diagram?
The Ishikawa diagram, also called cause and effect diagram or fishbone diagram, is a graphic organizer that represents the different causes of a problem with the aim of finding a solution, or a fact, with the aim of knowing what events produced it.
This diagram was invented around 1940 and was later improved by Kaoru Ishikawa, a Japanese-born chemist and business administrator, to analyze the different factors involved in a business process and determine which ones cause a problem.
Once the element generating the problem is detected, it is possible to propose a solution to improve the quality of a service or a product, achieve efficiency in a process or achieve an objective.
Although this diagram is mainly used in business and institutional settings, it can also be used in science and education to understand the causes of a phenomenon or explain different topics.
See also: Graphic organizers
What is the Ishikawa diagram for?
The Ishikawa diagram is used to:
- Analyze the management and organization of a company or institution. You can see what factors intervene in each area of a company with the aim of improving a production process.
- Control the quality of a product or service. You can analyze which factors generate quality problems in the development of a product or service to solve them.
- Analyze the sales sector of a company. The factors involved in each stage of the sales sector can be analyzed to improve the drawbacks of this area.
- Analyze the customer service sector of a company. The factors involved in this sector can be analyzed to adapt it to the needs of customers.
- Browse items linked to the marketing or marketing. You can analyze the different factors that intervene in the production of value of a product or service.
- Analyze processes. All the steps involved in a process can be analyzed in detail to improve it or solve a failure.
- Browse projects. Projects that will be carried out later can be analyzed in order to detect their possible drawbacks.
- Analyze the profitability of a business. The different factors that intervene in the profitability of a company or a store can be examined to identify how costs can be reduced or greater profits obtained.
- Analyze goals and objectives. You can analyze which factors do not allow you to achieve a goal or objective in order to solve them and make a company more competitive and efficient.
- Explain topics at different educational levels. Historical facts and natural and social processes can be explained when it is necessary to refer to multiple causes.
- Discover the causes of a phenomenon in research. Hypotheses can be made regarding the possible causes of a phenomenon in the social, natural or formal sciences, such as sociology, medicine and physics.
Ishikawa diagram structure
The structure of the Ishikawa diagram imitates the shape of a fish since the elements are distributed in different lines that resemble the spines of this animal.
These lines allow the main and secondary causes to be analyzed with a great level of detail and to include elements that were not considered pertinent or relevant, but that may be the true reason for a problem.
Elements of the Ishikawa diagram
The elements of the Ishikawa diagram are:
- Head. It is located on the right, can be in the shape of a fish head, a circle or a rectangle, and is the part where the problem, event or effect is written.
- central spine. It is a line that comes from the head.
- main spines. They are diagonal lines that emerge from the central spine and contain the main causes, categories or factors.
- secondary spines. They are lines that emerge from the main spines and contain the causes or secondary factors.
What are 6M?
The 6M are the six factors, categories or main causes that intervene in any productive or organizational process and from which the secondary causes emerge.
Analyzing the 6M is very useful when you want to solve a problem, because it allows you to visualize factors that otherwise would not have been taken into account.
The 6M are:
- Method. It includes the procedures of a process to produce a product or service. In addition, other aspects are taken into account, such as the time of each task and safety regulations.
- Machinery. It includes technological elements, that is, machines, physical and digital tools, their usefulness, their efficiency, their repair, their spare parts and their inputs.
- Labour. It includes people who participate in a productive or organizational process. Their knowledge, qualities, roles and responsibilities are also taken into account.
- Material. It includes the elements used to produce a product or provide a service. In addition, it takes into account its characteristics, its suppliers, its storage, its performance and its waste.
- Measurement. It includes the evaluation of the different parts of the process and the state of the machinery and materials.
- Environment. It includes a detailed analysis of the place where a production process is carried out. It takes into account different aspects, such as climate, cleanliness, pollution, light and the size of the site.
In addition to the 6Ms, other main factors can be included, such as investments, capital and market.
How to make an Ishikawa diagram?
To make an Ishikawa diagram, you can follow a series of steps:
- Determine what the problem is. You must indicate the problem for which you want to know its causes or factors. This item is placed at the head of the diagram.
- Brainstorm to identify the causes. People specialized in each area of the production process must participate in this process, but also others who are external, since they can provide a different point of view. All ideas are written down in a list.
- Trace the central spine. A line is drawn that starts from the head to the left.
- Draw the main lines. Lines are drawn starting from the central spine and the categories or factors are noted, which may be the 6M or others that are considered relevant.
- Draw secondary lines. Lines are drawn that come out of the main ones. In this step, the brainstorming elements are classified into some category.
- Analyze what factors cause the problem. Within each category, it must be determined which elements influence the problem. Those that are the causes of the problem can be painted red and those that are not can be painted green.
- Propose solutions for the causes of the problem. There should be a discussion about how the factor(s) causing the problem can be improved. Once a solution is implemented, it's a good idea to track it to see how it's progressing.
Examples of the Ishikawa diagram
1. Ishikawa diagram on a product
2. Ishikawa diagram of customer service
3. Ishikawa diagram of water pollution
4. Ishikawa diagram of restaurant service
Ishikawa diagram of the causes of World War I
Advantages and disadvantages of the Ishikawa diagram
The Ishikawa diagram has great advantages:
- It allows you to detect the possible causes of a problem, even those that are not obvious.
- It serves to organize difficult information, since different factors or elements can be classified into different categories and can be easily observed.
- It is a starting point to find solutions to different problems.
- Promotes exchange between staff and different areas of a company or institution.
- It can be applied in different sectors, such as business, institutional and educational. In addition, it can be implemented in the analysis of personal projects.
- It is very versatile, because it can be used to analyze problems or events of the present, but also of the past or future.
However, it also has disadvantages:
- It can produce bias, that is, an analysis or measurement error.
- It may not have all the necessary classifications and, therefore, leave out important factors.
- It only serves to analyze a problem at a certain time and, therefore, does not allow us to see changes.
- It can be difficult to create or take a long time to complete.
- You may be confused with labor factor analysis for fear of criticizing others about their work.
- It may not be sufficient to include all effects and causes.
References
- Acuña acuña, J. (2012). Quality control. Technological Editorial of Costa Rica.
- Andrade, AM, César, A. d. R and Alvear, DL (2019). Study of Times and Movements to Increase Efficiency in a Footwear Production Company. Technological information, 30(3), 83-94. https://dx.doi.org/
- Lazzati, S. C. (2013). Decision making: principles, processes and applications. Granica.
- Luconi Esquivel, T., Sandoval Atán, F and Alcázar Román, J. (2023). The relevance of considering all productive factors in quality analysis. Logos, 4(2): 177-184. http://dspace.ulead.ac.cr/
