Evaluate the Effect of Changes

Once the changed process is deployed across the project, the effect of the changes must be checked to gather evidence that the process change has corrected the problem and improved performance.

• Measure the change in the performance of the project's defined process as appropriate. This subpractice determines whether the selected change has positively influenced the process performance and by how much. An example of a change in the performance of the project’s defined design process would be the change in the defect density of the design documentation, as statistically measured through peer reviews before and after the improvement has been made. On a statistical process control chart, this would be represented by a change in the mean.
• Measure the capability of the project's defined process as appropriate. This subpractice determines whether the selected change has positively influenced the ability of the process to meet its quality and process-performance objectives, as determined by relevant stakeholders. [PA155.IG102.SP102.SubP102.N101] An example of a change in the capability of the project’s defined design process would be a change in the ability of the process to stay within its processspecification boundaries. This can be statistically measured by calculating the range of the defect density of design documentation, as collected in peer reviews before and after the improvement has been made. On a statistical process control chart, this would be represented by lowered control limits.