Quality Control vs Quality Assurance: Everything You Need to Know


Are the terms quality control and quality assurance confusing to you? Read on to learn exact differences between quality control vs quality assurance.

Quality is a key factor in business, especially for small businesses. Quality products help maintain customer satisfaction and loyalty. It also reduces the risks and cost of replacing faulty goods.

Quality management systems include two key components: quality control and quality assurance construction. Below, you’ll learn the differences between QA and QC.

Quality Assurance and Quality Control: Where Their Similarities Lie

Before we dive into quality control vs. quality assurance, let’s talk about what they have in common. Quality assurance (QA) and quality control (QC) are parts of quality management. They share one goal to remove defects or flaws.

All stakeholders in a company want QA and QC to reach this goal. They understand that customers want a product or service that meets expectations. High-quality products and services also attract customer loyalty, which makes a business profitable.

QA and QC also affect all other aspects of operations. This includes effective communication within a company, management, and data tracking. With that said, you can say that QA and QC determine customer happiness.

What Is Quality Assurance?

Now, let’s talk about quality assurance and its functions as a part of the quality management system. It is a part of the ISO 9000 set of international quality management standards. It helps companies meet compliance requirements, please customers, and improve processes and procedures.

Before a product can reach the QC team, it first undergoes quality assurance. QA is the process used to ensure that the project team is operating on the best practice principles. These principles help prevent the creation of unknown bugs and issues.

The QA functions to look at the procedures during product development or manufacturing. It aims to identify and address possible problems before they can happen.

In other words, QA works to improve the process to prevent bugs and defects in the product.

You can apply quality assurance in everything from manufacturing to software development. It’s also applicable to your processes, no matter how small or large your company is. Some trends in quality assurance and testing include AI-powered testing and performance engineering.

Approaches or Methods of Quality Assurance

In QA, you can use a variety of methods and activities. A QA team can make use of one or more of them. Below are the three approaches used in QA:

Failure Testing

You may know of the stress tests used in a variety of products, like smartphones. Failure or stress tests are methods of uncovering potential product weaknesses early. In a stress test, the testers will operate the product until it fails.

Often, they also operate the product in stressful conditions. This includes testing in an environment with high temperatures, speed, or humidity. Testers will increase the traffic, data, and usage for virtual products, like websites.

The collected data helps them deliver improvements to the manufacturing or engineering processes.

Total Quality Management (TQM)

The concept of Total Quality Management originated in the 1950s. TQM aims to involve all levels of functions in a company to meet and exceed buyer expectations. It doesn’t only improve product quality, but also efficiency, productivity, and teamwork.

When you practice TQM, you must consider several fundamental principles, including:

  • Customer focus
  • Commitment from the leadership
  • People engagement
  • Process approach
  • Relationship management
  • Evidence-based decision making; and
  • Continuous improvements

A famous example of TQM is Toyota. Toyota implemented the Kanban System, which made its assembly line more efficient. This allowed Toyota to keep enough inventories for customer orders as they came.

Standards and Models

You can find many models and standards for TQM that provide a regulatory framework for QA. An example is ISO 7025. It specifies what testing and calibration laboratories need to get accreditation.

Another example is the Capability Maturity Model Integration or CMMI model. It’s used as a quality-improvement tool by organizations and government agencies. The CMMI is a process and behavioral model.

Statistical Process Control (SPC)

You can also use statistics to observe behavior and find issues and solutions. Using SPC can also help you determine out-of-control events. With this approach, you use key tools like run charts, control charts, and more.

What Is Quality Control?

Now, let’s take a closer look at quality control. Quality control is the step in the process that identifies and improves defects. It is the stage wherein you conduct tests and inspections.

In QC, a quality examiner will use analysis and statistical sampling to test the product. This output can be the end-product or service provided by the company. QC ensures that the outcome meets the benchmarks to disapprove or approve the output.

In QC, a variety of activities occur and get observed. These activities include the production process, storage, and transportation. Each of these activities has a direct impact on the quality of the output.

The government and state guidelines may require businesses to manage quality control records.

Tools Used by a Quality Circle

Quality Circle is a group of people who analyze, identify, and solve defects. They use a variety of tools to aid them in reaching their goals and accomplishing their tasks. Those tools include:

  • Checklists
  • Fish-bone diagram
  • Control chart
  • Scatter diagram
  • Histogram
  • Pareto chart
  • Stratification

QC inspectors use some of these tools to examine the services or products. They use the results to determine which areas need improvement.

Quality Control vs Quality Assurance

Now, let’s take what we learned about QA and QC and compare them.

QA is a proactive step, while QC is a reactive move. QA prevents defects before they occur by improving process design. QC aims to identify defects after they’ve happened or after the output gets manufactured.

Another big difference between QA and QC lies in what they measure or assess. QA focuses on control systems, methods, and procedures to safeguard product quality. In QC, inspectors measure the outputs of the system, their parts, and functions.

When you look at QA, you’ll notice that it is a process-oriented process. QC focuses more on the product and finding issues with them. You can also frame these orientations as “action vs. results.”

When you look at the personnel involved in maintaining QC, you’ll find a dedicated team. However, in QA, it’s a company-wide effort. QA activities also improve the standards for training, documentation, and review.

QA is the technique of managing quality, while QC is a technique used to verify quality. In other words, QA handles the development cycle. QC manages the testing and output of that cycle.

These two factors work together to ensure that each product you bring out has the best quality.

For example, you’re developing SARMs for sale. Your QA process will include the planning for the creation and manufacturing process. Meanwhile, your QC executes the process and ensures the output passes standards.

Why Does Quality Control Matter If You Can Perfect QA?

A study found that 41% of consumers returned a non-defective item from 2018 to 2019. Each year, defective product returns create a $17 billion loss in revenue for retailers. Brick-and-mortar and online retailers often lose the most revenue from defective product returns.

The most returned product type were small home appliances, like blenders and coffeemakers. They’re followed by entertainment products, like TVs, gaming consoles, and speakers. Small gadgets, phones, tablets, major utility appliances, and home office products followed.

To avoid this, let’s say you perfected your quality assurance. You did everything necessary to make sure the planned process is seamless.

The question is, will you still need quality control if you do this?

The answer is yes. You will still need quality control, even if you’re confident that your QA plan is impeccable. QA and QC work better as two halves of a whole, rather than complementary steps.

Quality assurance doesn’t guarantee the quality of the end product. It only creates solid processes and aims to ensure they’re followed. This means that QA focuses on the operations, not the products or their actual quality.

You can say the same for quality control. Even the best QC will not guarantee that your outputs will always emerge at high quality. If you focus on the product, your processes won’t be consistent to ensure quality outputs.

Origins of Quality Management in Medieval Europe

Before modern quality management, medieval manufacturers already understood why quality was important. In medieval Europe, craftsmen organized into the late 13th-century guilds. The guilds they joined developed strict rules for service quality and product.

They enforced these rules by creating inspecting committees. These committees would specify which goods were flawless or of high quality with a symbol or mark. Craftsmen also often put a second mark, which tracked the start of faulty goods.

Over time, this mark changed and came to stand for a craftsman’s good reputation. Master craftsmen and inspection marks soon became the evidence of quality for consumers. This approach continued and remained dominant until the end of the Industrial Revolution.

Quality Management in the US

In the early 19th century, US manufacturing followed the model craftsmanship in Europe. Most craftsmen at the time marketed their goods to locals. They also inspected the quality of their goods before getting sold.

When the factories emerged, it forced craftsmen to work in them. These factories still ensured the quality of the products. They audited and inspected the products and scrapped or reworked defective outputs.

By the late 19th century, Frederick Taylor increased productivity without hiring more craftsmen. This rise in productivity created a dip in quality. Inspection departments got created to remedy the issue.

Quality Management During World War II

During WWII, the government enacted laws to push civilians to aid military production. Quality management became a decisive component of the war and a key safety issue.

The US armed forces inspected each unit created to ensure it was safe for handling. This created the problem of finding and keeping competent inspection personnel. To fix the issue, the armed forces renew unit-by-unit inspection with sampling inspection.

The armed forces adapted sampling tables with the help of industry consultants. They also sponsored training courses so that suppliers could improve product quality.

Quality Management in the Twentieth Century

Before the 20th century, you’ll notice that craftsmen didn’t give much focus to processes. At the turn of the century, processes began to appear in quality practices. These “processes” are a group of activities that take an input, add value to it, and provide an output.

In the mid-1920s, Walter Shewhart concentrated on developing controlling processes. This marked the start of the development and planning of processes for production. Focusing on the product was no longer enough to ensure quality and consistency.

Shewhart also laid the foundation for control charts. He acknowledged that industrial processes could yield data, which he can analyze. He used statistical techniques to examine whether a process was stable and controlled.

Later, W. Edwards Deming used Shewhart’s SQC methods. He became the head of the quality movement in the US and Japan. He was a statistician in the US Department of Agriculture and Census Bureau.

Examples of QA and QC in Various Industries

Certain strategies get used to detect physical contaminants in food production processes. They ensured that the contaminants get removed before the products leave the factory. In quality control, inspectors take food samples and look over them in labs.

In the pharmaceutical industry, companies review documents and review training records. They also review manufacturing records and approve equipment calibration to ensure quality assurance. To perform quality control, they’ll test for factors like the purity of a batch of drugs.

Find the Perfect Balance Between Quality Assurance and Quality Control

These are the differences between quality control and quality assurance.

We hope our quality control vs quality assurance guide was helpful. Now, you know what makes the two terms different, and you can use them without interchanging them.

Do you want to keep learning about quality management? Are you interested in seeing other content that tackles QA and QC? Check out our other guides now to see other content like this one.


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