Quality Assurance vs. Quality Control

The terms quality assurance and quality control are often interpreted differently by different people. This confusion is most likely a result of the multiple definitions for the words “assurance” and “control.”  

Let’s further explore the meanings of quality, assurance, and control.

Quality 

Quality can be thought of as a standard which is used to form a certain level of requirements, and to pursue a degree of excellence. 

When it comes to the success of a business, ensuring consistently high quality products and services offered is critical to long-term success. 

Assurance 

Assurance refers to the act of giving confidence, the state of being certain, or the act of making certain.

Control

Control conveys the meaning of an evaluation to indicate needed corrective responses, the act of guiding, or the state of a process in which the variability is attributable to a constant system of chance causes.

By conducting quality assurance and quality control practices, organizations can gauge where various levels of quality lie, and identify areas where more attention and resources are required.

While quality assurance and quality control are often used interchangeably to refer to the actions performed to ensure the overall quality of a product, service, or process, there are differences in their definitions that should be both acknowledged and considered.

Defining Quality Assurance (QA)

The International Organization for Standardization, commonly known as the ISO, develops and publishes standards that are recognized and observed around the world. 

The ISO 9000 family addresses various aspects of quality management and contains some of ISO’s best known standards. 

These standards provide guidance and tools for organizations that want to ensure their product and services consistently meet customers’ requirements, and that quality is consistently improved upon.

According to ISO 9000:2015: Quality management systems—Fundamentals and vocabulary, quality assurance consists of that “part of quality management focused on providing confidence that quality requirements will be fulfilled.” 

Think of quality assurance as a catch-all litmus test that all of an organization’s processes, procedures, products, and services go through. 

By performing QA, the organization can be confident that the end result has met or exceeded their standard of quality.  

Quality Assurance in Software

According to The ISO, in software, quality assurance refers to:

“The function of software quality that assures that the standards, processes, and procedures are appropriate for the project and are correctly implemented."

Quality Assurance is a Preventative Measure

The purpose of QA is to prevent defects or known bugs from hitting the market. It provides the opportunity to correct these issues before a release or update goes live.

Simply put, quality assurance is a proactive management practice used to ensure that quality standards are met or exceeded. 

QA planning is conducted at the beginning of a project. Typically, the outcomes of QA planning initiatives are quality plans, inspection and test plans, the selection of defect tracking tools, and the training of people in the selected methods and processes.

By conducting QA at the beginning of a project, businesses can mitigate identified risks before they negatively impact the business or disrupt customer experiences. 

Defining Quality Control (QC)

According to ISO 9000:2015: Quality management systems—Fundamentals and vocabulary, quality control is that “part of quality management focused on fulfilling quality requirements.

While QA addresses how a process is performed or how a product is made, quality control addresses more of the inspection of the end product or service. 

In layman's terms, QC is a reactive method by which quality is gauged and consistently monitored.

Quality Control in Software

According to The ISO, in software, quality control refers to:

"The function of software quality that checks that the project follows its standards, processes, and procedures, and that the project produces the required internal and external (deliverable) products."

Quality Control is a Detection Mechanism

QC refers to the verification of output conformance to desired quality levels. It’s used to isolate and provide feedback on the causes of quality problems.  

Contrary to quality assurance, quality control includes all activities that serve the purpose of determining the level of quality delivered by the solution, product, or service at hand.

Before a project goes into production, stakeholders should consult with customers to identify customer requirements expected from the product or service. These customer requirements can then serve as a checklist that can be monitored throughout the development lifecycle of the product or service.

QC can then be performed by using processes such as structured walkthroughs, testing, and code inspections to ensure that the product or service offering meets the agreed set of requirements.

Both Quality Assurance and Quality Control Are Components of Quality Management

QA addresses the process of quality, while QC addresses the quality of output, or the end product itself.

Businesses must allocate appropriate resources for the consistent performance of quality assurance and quality control in order be confident that they are offering the best products and services possible, and meeting the expectations of their customers. 

Both of these tactics fall under the larger umbrella of quality management -- the process of ensuring that an organization, product, or service remains consistent in their fulfillment of quality standards.

As an organization’s quality management plan evolves over time, the confidence of all stakeholders -- including employees and customers -- will also grow.

According to ISO, quality management is comprised of seven core principles:

  1. Customer Focus

  2. Leadership

  3. Engagement of People

  4. Process Approach

  5. Improvement

  6. Evidence-Based Decision-Making

  7. Relationship Management


Read ISO’s paper on Quality Management Principles for more information on each of these principles.

The Benefits of Using Surveys for Quality Management

Many benefits come with implementing surveys into your organization’s overarching quality management strategy. 

These surveys can be used to inquire about, and identify the customer requirements discussed above in regard to quality control. 

Further, if surveys gauging quality are distributed to customers on a consistent and routine basis, businesses will be able to identify and define trends, and find the root-cause of problems that may lead to decreased quality over time. 



The insights gathered from this data can inform and set the pace of strategic development, as well as help product teams prioritize their efforts. 



If customers see that their feedback is not only being considered, but acted on, the business will see a spike in customer satisfaction and loyalty, which of course, can be measured with the Net Promoter Score (NPS).  

In the long-term, businesses that leverage surveys as part of a greater comprehensive quality management strategy will see a positive impact on their bottom-line. 

These businesses will also end up spending less capital thanks to new efficiencies created by quality management processes. 


What does your organization’s quality management strategy look like? We’d love to hear from you! Drop us a line in the comments below.