Quality Assurance vs Quality Control

The difference between Quality Assurance and Quality Control is one of the most frequently asked questions and among the most commonly confused concepts for the PMP exam. Going by the emails and comments I receive, I’m sure many of you are interested in this topic. In this post, we’ll look at the differences with the help of a quiz.

PMBOK^® Guide, 5th Edition definitions of QA and QC

First let’s look at the PMBOK^® Guide, 5th Edition definitions of Quality Assurance (QA) and Quality Control (QC). Note that the formal names of these processes in the PMBOK Guide are Perform Quality Assurance and Control Quality.

Perform Quality Assurance

Accordingly to the PMBOK^® Guide, 5th Edition, Perform Quality Assurance is the process of auditing the quality requirements and the results from quality control measurements to ensure appropriate quality standards and operational definitions are used.

Control Quality

Control Quality is the process of monitoring and recording results of executing the quality activities to assess performance and recommend necessary changes.

Simplified Explanation

Let’s look at the simplified definitions next.

Difference between Quality Assurance and Quality Control

Quality Assurance checks whether quality standards are being followed, whereas Quality Control checks whether quality standards are being met. Audits and root cause analysis are examples of QA. Peer reviews and testing are examples of QC.

In QA think about “process”, and in QC think about “deliverables”.

Quality Assurance and Quality Control Quiz

I’ve got a simple quiz for you. All you need to do is to match a given term with the process it’s most closely associated with.

HINT: Some terms are associated to both Quality Assurance and Quality Control.

Good luck.

Questions

Answers

Thanks for the overwhelming response to the Quiz and the awesome suggestions for blog topics. As of 7/14/2017, this quiz has received 1060 responses. I really appreciate the response. Let’s review the answers to the questions. Feel free to question the answers!

1. Deliverable - Quality Control

Quality Control is about reviewing the deliverables to ensure that quality standards are being met.

2. Process - Quality Assurance

Quality Assurance is about the process used for creating the deliverables.

3. Peer Review - Quality Control

Peer reviews are usually performed as part of quality control. They are very common in software development projects.

4. Fishbone Diagram - Quality Assurance, Quality Control

Fishbone Diagrams can be used in Quality Control to identify the factors contributing to potential quality problems or effects. Fishbone diagrams can also be used in Quality Assurance to identify the root cause of problems.

This is one question that stumped most people.

5. Audit - Quality Assurance

Audits are done to ensure that the quality standards established in the project plan are followed.

6. Quality Control Measurements (as input or output) - Quality Assurance, Quality Control

Quality Control Measurements are an output of Quality Control, and an input to Quality Assurance.

7. Usually done by a group external to the project - Quality Assurance

Quality Assurance is usually performed by the Quality Assurance department or a group external to the project team. Quality Control can be performed by a Quality Control department (which can be external too), or can be done by the project team.

8. Are the standards being followed? - Quality Assurance

Quality Assurance ensures that quality standards are being followed.

9. Are the standards being met? - Quality Control

Quality Control checks whether standards are being met.

10. Right First Time - Quality Assurance

Right First Time or Zero Defects is Step 7 of Phil Crosby’s 14 Step Quality Improvement Process. Quality Improvement is usually associated to Quality Assurance.

11. Proactive - Quality Assurance

Quality Assurance tries to prevent problems, and hence considered proactive.

12. Reactive - Quality Control

Quality Control finds the problems after the problems have occurred, and hence reactive.

13. Capability Maturity Model Integrated (CMMI®) - Quality Assurance

CMMI is a process improvement model and associated to Process Analysis, which is a technique used in Quality Assurance.

14. Find defects - Quality Control

Quality Control finds defects.

15. Prevent defects - Quality Assurance

Quality Assurance helps to prevent defects.

16. Root Cause Analysis - Quality Assurance

Root Cause Analysis is a part of Process Analysis, which is a technique used in Quality Assurance. This is a question that most people got wrong.

17. Metrics - Quality Assurance, Quality Control

Quality Metrics are an input to both Quality Assurance and Quality Control. This question is straight from the PMBOK Guide, but received only 50% correct responses. So, please do NOT ignore the PMBOK Guide.

18. Executing Process Group - Quality Assurance

Quality Assurance is a part of Executing Process Group, whereas Quality Control is a Monitoring and Controlling process.

19. Quality Checklists - Quality Control

Quality Checklists are an output of Plan Quality and an input to Quality Control.

20. Cost Benefit Analysis - Quality Assurance

Cost-Benefit Analysis is a technique used in Plan Quality, but can also be used in Quality Assurance. Note that all Plan Quality and Quality Control tools and techniques can be used in Quality Assurance also.

Refer to the graph below for a quick snapshot of the quiz results by questions:

Please let me know your comments and suggestions. I welcome all feedback.

Image credit: >Flickr / SMJJP