Quality control focuses on measuring the results of the project work throughout the entire project life cycle to ensure that work is done in accordance to the quality plans and characteristics.  The end product or service must align with what the customer expected and what was documented in the project documentation.

It is important to note that quality assurance focuses on developing and implementing quality related processes and activities while quality control focuses on ensuring that results from quality tasks achieve their desired objectives (examples of control focus on validation, verification, defect management, preventive maintenance, etc).

Quality   Systems
Quality control systems are a collection of formalized processes to help measure specific project results and confirm how they align to the project quality standards established.  The project team must ensure the level of quality required is understood by all stakeholders and is also realistic when aligned with project constraints (e.g. resources, time and budget).  The quality system should evolve as the project complexity changes and work is completed and thus requires reviews on the effectiveness, efficiencies and value (in alignment with the project objectives and stakeholder needs).  Example aspects of a quality control system include:
  • lists and describes the quality characteristics and measurements that are required as part of the project;
  • coordinates tasks and help resources execute, monitor, control and close them;
  • supports resources with the tools and functionality to facilitate information collection, analysis and calculations;
  • empowers people to take an active role in quality;
  • provides detailed comparisons with actuals verses planned in terms of quality characteristics and specific measurements;
  • supports the organization to help shift the culture, attitude and understanding of quality.

Quality Methods
There is much quality research and expertise available (e.g. National Quality Institute, Malcolm Baldrige, ISO 9000 series, European foundation for quality management, etc.). 

Two of my favourite quality graphing tools include (LOVE graphs, humans love to see visual displays in combination with hard data, tell them what the results are and what they mean, then show them visually and let it sink in):
  • control chart – line graph that illustrates the results and control limits (mean, upper control and lower control limits);

  • pareto chart – bar chart displayed by order of severity (80/20 rule);

Other examples include:
  • histogram – graphical display utilizing bar charts;
  • run chart – run charts showing trends;
  • scatter diagram – correlation between 2 variables;
  • statistical methods and formulas;
  • flowchart;
  • cause and effect diagram;
  • checklist;
  • inspection;
  • test;
  • defect repair review.