If 5 defects were found during a software analysis and 5 defects were found in...

Phase containment effectiveness measures how well a development or review phase finds defects before they escape to later phases. It is commonly calculated as defects found in the phase divided by the total defects associated with that phase, including defects found in the phase and defects that escaped to later phases. In this case, 5 defects were found during software analysis and 5 additional defects were found later. Therefore, PCE equals 5 divided by 10, multiplied by 100, which is 50%. A result of 100% would mean no defects escaped. A result of 0% would mean none were found in the phase. Since half were contained and half escaped, the correct answer is 50%.

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