DRE = Defects removed during a development phase/ Defects latent in the product at that phase x 100%
Defect Removal Effectiveness can also be calculated for the entire development cycle to examine defect detection efforts before the product is released to the field. According to Capers Jones, world class organizations have Development DRE greater than 95%.
Development DRE = (Pre-release Defect) / (Total Defects) x 100% = X%
The longer a defect exists in a product before it is detected, the more expensive it is to fix knowing the DRE for each phase can help an organization target its process improvement efforts to improve defect detection methods where they can be most effective. Future DRE measures can then be used to monitor the impact of those improvement efforts.
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