Code Inspection: why, when and what
When should you inspect software?

We advise you to inspect code during development AND before testing:

Inspect during development—Software maintenance starts from day one of a project and inspected software is less expensive to alter, fix and maintain. This statement is founded upon these research findings:

Inspect before testing—Software should be inspected before it is tested: when it comes to finding defects, inspection is much cheaper and faster. This statement is founded upon these research findings: