Project Quality Management : Peform Quality Assurance Vs Perform Quality Control

One of the most common mistakes that most test takers make is to confuse between the two processes in Project Quality Management i.e Perform Quality Assurance with Perform Quality Control.  However it is quite natural for us to make this mistake since the difference between the two processes are subtle.  Unless a person works in this field,  it is difficult for him to understand how both these processes work and what are the fundamental differences  between the two. The PMP® certification exam has quite a few questions based on these two processes and understanding these processes well could help us in getting the right answers for those questions.

Basic Concepts in Quality Management 

Before we take a look at these two processes let us first understand a few concepts of quality management which will enable us to understand these two processes better. They are "Prevention over inspection" and "DIRFT - Do It Right the First Time".  At the heart of both these concepts lies the idea that whatever we deliver should be delivered error free from the start of the project. It is quite costly to fix an error later on in the project. Now, how is it possible to ensure that our deliverables are error free ? The answer is simple : We have to put the appropriate processes in place which can help us in producing an error free deliverable every time a deliverable is produced. However, there will always be some deviation even from the best processes.  That is why we also have to put some controls in place which can measure the results so that we can make any adjustments if necessary.

Therefore, quality assurance is all about processes that are used for preventing any defects and quality control are the measurements we have in place to detect and repair any remaining defects.

Let us now take a look at each of these processes individually to understand them better

Perform Quality Assurance

The perform quality assurance is an executing process and it is primarily concerned with overall process improvements to ensure that each time a deliverable is produced it is error free. If the quality of the processes and activities is improved, then the quality of the product should also improve along with an overall reduction of cost. Quality Assurance begins very early and continues throughout the life cycle of the project. Since this process uses some of the outputs of plan quality process, it is not performed until after Plan Quality is performed.

Quality Audit is a key tool used in this process. Quality audits enable us to review the project to evaluate which activities taking place in the project should be improved and which meets the quality standards. Quality audits has dual objectives in improving acceptance of the product and improving the overall cost of quality.

The quality assurance department performs these audits periodically as a part of the executing process looking at the quality control measurements to see if there is any indication that the standards, policies, plans and procedures are not being followed or the procedures are not producing the expected quality results . This department also issues change requests including notifications of areas that need preventive actions, corrective actions and defect repair. In addition to this, the quality assurance department looks for project best practices or improvements to processes that can be used throughout the organization.

Perform Quality Control

The perform quality control is a monitoring and controlling process and it looks at specific results to determine if they conform to the quality standards. This process involves both, the project and product deliverables and it is done throughout the project life cycle .

This process typically uses statistical sampling rather than looking at each and every output. There are a lot of sampling techniques which are used in various industries and the practice is often very complex and tailored to each industry. The quality control process uses the tool of inspection to make sure the results of the work are what they are supposed to be. This process makes sure everything that is produced meets quality standards.

This process is performed beginning with the production of the first product deliverable and continues until all the deliverables have been accepted.

The quality control department measures the performance of the project from the start of planning to the projects end against the standards, policies, plans and procedures. As a result of these measurements, the department also issues change requests including notification of areas that needs preventive actions , corrective actions or defect repair.

Let us take a look at an example to understand the two processes better.


Let us assume that we are manufacturing laptops. In Quality Assurance we need to put all the processes in place to ensure that each laptop is manufactured defect free.This would include the types of manufacturing equipment used, training people and documenting all production processes.Quality Control comes into play after the fact by testing the finished product. For instance we can do a sample testing to see if a randomly picked laptop from our production line passes or fails the quality standards.


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About the Author


Sabyasachi has over a decade’s experience in leading IT and non IT projects in the Healthcare, Oil and Energy, eCommerce, Public Sector Undertaking , and Services industry . He is a PMI certified Project Management Professional , PMP, and a volunteer in the Project management community with a focus on best practice and mentoring other project management professionals . His writings are regularly published in several blogs , forums and online project management communities .

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