Although sometimes used interchangeably, Quality Control and Quality Assurance are distinct terms. What is the difference between these two? We’ve created a brief QA vs QC comparison to break it down for you.
Keeping things clear and transparent is essential for the Product Managers and other people involved in the delivery process. The fact that the team members understand a particular concept differently may create unnecessary confusion or even compromise the project’s safety. Thus, it’s worth making sure that you’re all on the same page – also in terms of QM’s concept of Quality Control and Quality Assurance.
Below, we explain the difference between Quality Control and Quality Assurance using the most common examples. But let’s start from the basics – by understanding quality management system better.
What is quality management?
QM is obviously not a new thing. Even the medieval practices – take the craftsman’s apprenticeship – have already contained elements of quality management. However, the rapid development of QM started during the industrial era, stimulated by mass production. The unprecedented scale of production processes has created a demand for new strategies for managing effectiveness and quality. The latter has become one of the key assets to outrun the competition. That has led to the development of statistical process control – a QM method created by Walter A. Shewhard in the 30s.
The use of statistical quality control by the Japanese market in the 50s – and speaking more precisely, Toyota’s emblematic quality management system – has given rise to quality management as we know it today. Currently, the companies usually follow the principles of Total Quality Management – a philosophy based on constant pursuit of improving processes and elements of the organization. International quality standards have an influence on the TQM, but the approach to regulating policies depends on the organization’s specifics.
Quality management principles include customer focus, leadership, engagement, process approach, improvement, evidence-based decision-making, and relationship management.
There are four components that constitute quality management systems:
Quality Control
Quality Assurance
Quality Improvement
Quality Planning
In our article, we’ll focus on the first two, since they’re frequently mistaken for each other. Generally, those who do not have any association with QM may consider the differences between these two domains quite vague. We’ll try to clarify them so that it’s easier for you to, for instance, choose a form of external support or define the vacancies in the recruitment process.
Quality Assurance vs. Quality Control
You may have seen these two terms being used interchangeably, but as we’ve already mentioned, they are not the same thing. In a nutshell, Quality Control is a part of all actions and processes defined as Quality Assurance. The fundamental differences between these two lie in:
1. The direction
The aim of Quality Assurance is to prevent the defects of different nature and any fall in standards. Meanwhile, Quality Control aims at verifying the presence of these issues and, eventually, their elimination.
2. The orientation
The purpose of the Quality Planning process is to identify the quality requirements of the particular project. Both components of QM – Quality Assurance and Quality Control – refer to these requirements, but in a different way. QC focuses on their realization and QA – on ensuring that they will be put into practice. Quality Control puts the emphasis on the product, while Quality Assurance is process oriented.
Quality Control vs Quality Assurance – how does it work in practice?
Does it still sound quite vague to you? We’re aware that this jargon may be confusing. Thus, let’s break this issue down using the example.
Let’s assume that your product is just before the release. If you want to know which aspects or features require some refining in this or the next software development life cycle, you should rely on the Quality Control activities. Collecting reviews and analyzing data collected by the performance management systems may help you reach the goal that is meeting the standards set up in the quality planning phase.
If you want to know which direction to take in the future in order to minimize the business risk and maintain the highest quality, you’ll need QA processes. By using different Quality Assurance tools, you can predict the changes of the process on the timeline with the use of historical data or identify variables that change the course of your project. You can also rank the risk factors using the Pareto chart. These methods, among others, will help you see the bigger picture.
There are many tools applied in Quality Management – we won’t list them all here. You can download ready-made templates in Excel that facilitate their implementation on the official ASQ website.
Wrap-up
As you can see, Quality Control and Quality Assurance are two distinct concepts, and both can help you with building customer’s trust. It’s also worth underlining that while the Quality Control is a domain of the trained quality testers, the Quality Assurance process usually engages all the team working on a particular project. The introduction of the quality management software is a great way to improve the QA processes, but the training is also essential.