The other day I was browsing online for documentation on Software Quality Management and related topics, and I have noticed that several definitions available are either too generic or very confusing. Although terms like “Quality Assurance” and “Quality Control” are relatively straightforward to understand, they end-up receiving very generic definitions when they are described without a clear context like “Software”, “Hardware” or a specific product industry. In this article, I try to give the simplest and most representative definitions I can give.
A common place to start looking for these definitions is the ISO 9000 set of standards .for Quality Management. This “family” standards “provide guidance and tools for companies and organizations who want to ensure that their products and services consistently meet customer’s requirements and that quality is consistently improved” [ISO 9000 Family]. Here, we can find clear definitions of the terminology needed for this context, including for “Quality Assurance” and “Quality Control”.
Let us take a look at the common definition of “Quality Assurance” we can find online:
A part of quality management focused on providing confidence that quality requirement will be fulfilled” – ISO 9000, Clause 3.2.10
I think part of the confusion with these terminologies starts here. As it was done in this article so far, the definition is taken out of the ISO broader context and the supporting information is not usually made available. From this definition alone it is not possible to understand what “Quality Management” or “Quality requirement” is. These terms are essential to concretely understand what is to be understood from this definition and have to be clearly defined as well.
The common definitions which are available for Quality Management are often something similar to:
Quality Management employes quality assurance and quality control processes to achieve consistency on the expected levels of quality.
The issue here, again, is that new terminologies are inserted and not often included in the context. Therefore, we define the most generic term at first, Quality Management.
David Hoyle (2017), defines quality management under two different categories, the “management of success” and the “elimination of failure” (these are terms we can understand without any extra definitions, right ?!). These definitions help us to understand what is the goal of quality management through the concrete perspective of what is expected in relation to “success” and “elimination of failure” of a project.
Management of success
- What are you trying to do?
- How do you make it happen?
- How do you know it’s right?
- How do you know it’s the best way of doing it?
- How do you know it’s the right thing to do?
Elimination of Failure
- How do you know what is needed?
- What could affect your ability to do it right?
- What checks are made to verify achievement?
- How do you ensure the integrity of these checks?
- What action is taken to prevent a recurrence of failure?
In practical terms, the achievement of consistent levels of quality depends on several different factors (e.g.: the answers of the questions above) and can be achieved through planning, assuring, controlling and improving.
- Planning, in general, includes the preparation of activities required to achieve a specific goal.
- Quality Assurance is the set of activities focused on what can be done to provide confidence that the outputs will meet its expectations
- Quality Control is where the product is inspected for failures
- Quality Improvement includes the set of efforts to systematically identify and define provisions for improving existing processes towards better quality parameters
Product requirement, in general, represents what the product “shall do” and “shall be”. Therefore, quality requirements can be (losely) defined as to which extent the product meets it’s customer needs.
Now, with a context established, it is easier to understand the definitions for Quality Assurance and Quality Control.
A part of quality management focused on providing confidence that quality requirement will be fulfilled” – ISO 9000:2005, Clause 3.2.11
Focus on the process to increase confidence pn levels of quality.
A part of quality management focused on fulfilling quality requirements
ISO 9000:2005, Clause 3.2.10
Focus on product inspections to identify failures.
This article describes Quality Assurance and Quality Control within the context of Quality Management in order to avoid confusion with these definitions when described without supporting contexts.
The information available in this article can be found in further detail in the ISO 9000 Family and in the (very good) book from David Boyle (see references).
- International Standard Organization, 2019 – ISO 9000 Family, – https://www.iso.org/iso-9001-quality-management.html (accessed 03/2019)
- D. Hoyle, 2017 – ISO 9000 Quality Systems Handbook-updated for the ISO 9001: 2015 standard: Increasing the Quality of an Organization’s Outputs