How to calculate Review Efficiency ?

Review Efficiency is the ratio of number of review defects to total number of defects in review and testing.  Review defects can be encountered in documents (e.g. test plan, test cases) as well as in code (e.g. unit, integration, system, function, procedures). Defects identified in review process costs lesser effort and amount to fixes it. It helps to decrease the defect leakage in subsequent later phases of testing stages.

It is measured at overall project level and stage level. It is measured in percentage (%).

How to calculate Review Efficiency:

Review Efficiency = (Total Number of Review defects) / (Total number of Review defects + Total number of Testing defects)*100

Example:

No. of Review defects	Total No. of Testing defects	Review Efficiency %
25	100	20

Review Efficiency = 25 / (25 + 100) * 100

                               = 20

Review Efficiency metric shows the efficiency of the review process in software testing. A higher ratio of Review Efficiency indicates better is the review process. If the ratio is low then is does not mean review process inadequate. When ratio is low then the project manager or team leader discuss with the team and work on Review Efficiency improvement.

Review Efficiency metric helps to know the review effectiveness and take action to improve the review process.

Note: The total number of Testing Defects includes all the defects including customer reported test defects.