Inspection

Definition

Inspection is a quality engineering technique during which a work product is formally evaluated against a checklist in order to identify defects.

Discussion

Inspections are the most effective quality engineering technique for identifying defects.

The typical objectives of inspections are to:

• Identify defects in a work product so that they can be fixed.
• Identify defects in a process so that they can be fixed and work product defects can be avoided in the future.

Preconditions

Inspections can typically begin when the following preconditions hold:

• The work product or process is ready for inspection:
  • The parts of the work product to be inspected are relatively complete and stable.
  • The process has been documented and has been in use of a significant amount of time.

Completion Criteria

Inspections are complete if the following postconditions hold:

• The inspection meeting has been held.
• The results of the inspection have been summarized.
• The individual inspection reports and the inspection summary report have been delivered to the development team and recorded.

Steps

During inspections, the following producers perform the following steps:

• The development team that produced the work product:
  • Schedule the inspections.
    Schedule the inspections and obtain a properly equipped location to hold the inspection(s).
  • Notify inspection team.
    Notify the inspection team of the date, time, and location of the inspection.
  • Provide work products.
    Provide the inspection team with copies of the deliverable work products to be inspected.
  • Clarify work products.
    Clarify the contents of the work products and answering the questions raised by the inspection team during the inspection.
• The Inspection Team:
  • Inspect work products.
    Individually inspect the deliverable work product(s) using the associated inspection checklists to identify defects.
  • Hold inspection meeting.
    Hold the inspection meeting with representatives of the development team to clarify questions raised during the individual inspection.
  • Summarize team findings.
    Summarize the results of the inspection on an inspection summary report.
  • Deliver team findings.
    Deliver the inspection summary reports and the individual inspection reports to the development team.
  • Recommend process improvements.
    Recommend improvements to the process regarding:
    • The activity and its associated tasks.
    • The standards, templates, and inspection checklists for the deliverable requirements work products.

Work Products

Inspections typically result in the following work products:

• Inspection Summary Report
• Inspection Report

Limitations

Inspections are subject to the following limitations:

• Although very effective, inspections are expensive to conduct.
• The inspection checklist needs to be regularly updated as the quality and process teams identify which defects are the most common or have the highest impact.

Guidelines

• Inspections may be performed incrementally and iteratively as the corresponding work products are developed. Where practical and cost effective, inspections should be incrementally performed on the parts of incomplete or interim work products that have stabilized.
• Inspections should be scheduled far enough in advance so that the inspection team has adequate time to inspect the work products.
• The scope of a single inspection can be one or more work products.
• The purpose of the inspection meeting is to answer questions and summarize findings, not to fix the defects found.
• Inspections should be performed on all work products before final delivery to the customer organization.