Total Quality Management (TQM) is a comprehensive approach to managing an organization’s operations to achieve continuous improvement in the quality of its products and services. As part of TQM, seven basic tools are widely used to identify, analyze, and resolve quality-related issues. These tools are:
Key Facts
- Stratification: Stratification analysis is a quality assurance tool used to sort data, objects, and people into separate and distinct groups. It helps in determining patterns and meaning in data.
- Histogram: A histogram represents the frequency distribution of data among different groups. It allows you to identify areas of improvement within your processes by visually displaying the distribution of data.
- Check sheet (or tally sheet): Check sheets are used to collect quantitative or qualitative data. They can be used to quickly zero in on defects or errors within a process or product, and identify patterns and causes of specific defects.
- Cause-and-effect diagram (also known as a fishbone or Ishikawa diagram): This tool helps in identifying the various factors or causes leading to a problem. It organizes causes into categories such as measurements, materials, personnel, environment, methods, and machines, making it easier to identify the probable source of the problem.
- Pareto chart (80-20 rule): The Pareto chart operates according to the 80-20 rule, which suggests that 80% of a process’s problems are caused by 20% of major factors. It helps in highlighting the relative importance of different parameters and focusing efforts on the factors with the biggest impact.
- Scatter diagram: The scatter diagram is used to depict the relationship between two variables. It helps in identifying cause and effect relationships and can be useful in quality control when defining relationships between quality defects and possible causes.
- Control chart (also called a Shewhart chart): Control charts help in determining whether a process is stable and predictable. By comparing historical data to data collected from the current process, it is possible to identify factors that might lead to variations or defects. This tool helps in predicting process performance and ensuring that it meets customer or organizational expectations.
Stratification
Stratification is a technique used to divide data into smaller, more manageable groups based on common characteristics. This allows for the identification of patterns and trends within the data that might not be apparent when examining the data as a whole. Stratification can be used to analyze various types of data, such as customer demographics, product defects, and process performance metrics.
Histogram
A histogram is a graphical representation of the frequency distribution of data. It displays the number of data points that fall within specified intervals, allowing for the visualization of the distribution of data and the identification of patterns and trends. Histograms are commonly used in statistical analysis and quality control to understand the variability of data and identify potential outliers.
Check Sheet (or Tally Sheet)
A check sheet is a simple data collection tool used to record the occurrence of specific events or defects. It consists of a list of items or categories, and each time an event or defect occurs, a mark is made in the corresponding category. Check sheets are commonly used in quality control to collect data on defects, errors, or other quality-related issues.
Cause-and-Effect Diagram (Fishbone or Ishikawa Diagram)
A cause-and-effect diagram, also known as a fishbone or Ishikawa diagram, is a visual tool used to identify and organize the potential causes of a problem or issue. It consists of a central line representing the problem, with branches extending from the line to represent the various factors that may be contributing to the problem. Cause-and-effect diagrams are commonly used in quality control and problem-solving to identify the root causes of problems and develop corrective actions.
Pareto Chart (80-20 Rule)
A Pareto chart is a graphical representation of the distribution of data, where the data is sorted in descending order of frequency or magnitude. The Pareto chart is based on the 80-20 rule, which suggests that 80% of the problems or defects are caused by 20% of the factors. Pareto charts are commonly used in quality control and process improvement to identify the vital few factors that contribute to the majority of problems and prioritize improvement efforts.
Scatter Diagram
A scatter diagram is a graphical representation of the relationship between two variables. Each data point on the scatter diagram represents the values of the two variables for a particular observation. Scatter diagrams are commonly used in statistical analysis and quality control to identify correlations between variables and to explore the relationship between them.
Control Chart (Shewhart Chart)
A control chart is a graphical tool used to monitor the stability of a process over time. It consists of a central line representing the average or target value of the process, with upper and lower control limits that are calculated based on historical data. Data points are plotted on the control chart, and if they fall outside the control limits, it indicates that the process is not stable and may require corrective action. Control charts are commonly used in statistical process control to monitor and maintain the quality of products and processes.
These seven tools are fundamental to TQM and are widely used in various industries and organizations to identify, analyze, and resolve quality-related issues. They provide a structured and systematic approach to problem-solving and continuous improvement, enabling organizations to enhance the quality of their products, services, and processes.
References:
- Seven Basic Tools of Quality – Lucidchart: https://www.lucidchart.com/blog/what-are-the-7-basic-quality-tools
- TQM Tools – University of Cambridge: https://www.ifm.eng.cam.ac.uk/research/dstools/tqm-tools/
- Seven Basic Tools of Quality – Wikipedia: https://en.wikipedia.org/wiki/Seven_basic_tools_of_quality
FAQs
What are the seven tools of TQM?
The seven tools of TQM are:
- Stratification
- Histogram
- Check sheet (or tally sheet)
- Cause-and-effect diagram (fishbone or Ishikawa diagram)
- Pareto chart (80-20 rule)
- Scatter diagram
- Control chart (Shewhart chart)
What is the purpose of the seven tools of TQM?
The seven tools of TQM are used to identify, analyze, and resolve quality-related issues. They provide a structured and systematic approach to problem-solving and continuous improvement, enabling organizations to enhance the quality of their products, services, and processes.
How are the seven tools of TQM used?
The seven tools of TQM are used in various ways to improve quality, including:
- Identifying and prioritizing problems
- Analyzing data to identify root causes of problems
- Developing and implementing corrective actions
- Monitoring and controlling processes to ensure they are stable and predictable
- Continuously improving products, services, and processes
What are the benefits of using the seven tools of TQM?
The benefits of using the seven tools of TQM include:
- Improved product and service quality
- Reduced costs
- Increased productivity
- Improved customer satisfaction
- Enhanced competitiveness
Which tool is used to divide data into smaller, more manageable groups?
Stratification
Which tool is used to graphically represent the frequency distribution of data?
Histogram
Which tool is used to identify and organize the potential causes of a problem or issue?
Cause-and-effect diagram (fishbone or Ishikawa diagram)
Which tool is used to graphically represent the relationship between two variables?
Scatter diagram