Design Reviews
Peer Reviews
Agenda
•
Peer Reviews
• Participants of Peer Review
• Preparation for a Peer Review Session
• The Peer Review Session
• Post-peer Review Activities
• Efficiency of Peer Review
• Peer Review Coverage
•
Comparison of Team Review Methods
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Peer Review
•
Peer Review method vs. Formal Design Review
 Authority – DR participants hold superior position to project leader; in PR,
the participants are equals to the project leader.
 Degree of Authority – DR can decide whether the project moves to the
next stage. Not the case in a PR
 Objective – PR objective is to detect errors and deviations
•
Methods of Peer Review
 Inspection
 Walkthrough
•
Inspection vs. Walkthrough
 Inspections are more formal than Walkthroughs
 Walkthrough findings are just comments whereas the findings in
Inspections are used to improve development methods.
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Inspections
•
Development of inspection checklist for each design
document.
•
Development of Defect Type Frequency Table – used by
inspectors to look for defect concentration areas.
•
Training of professionals in the Inspection process.
•
Periodic analysis of the effectiveness of past inspections.
•
Introduction of scheduled inspection into project activity
plan.
4
Participants of Peer Review
•
Optimal team is 2-5 participants (1-3 can be added)
•
All participants are peers (equals) of the system
designer
•
Review Team includes
 Review Leader
 The Author
 Specialized Professionals
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Participants of Peer Review
•
Review Leader
 Known as moderator in Inspections and coordinator in Walkthroughs
 Should know about development of projects of the current type and
familiar with technology
 Has good relationship with the Author and the Development Team
 Not a member of the Project Team
 Experienced in coordination and leadership
 Should be a trained moderator – moderate meetings
•
Author
 Participant in each type of the peer review.
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Participants of Peer Review
•
Specialized Professionals - Inspection
 Designer: System analyst responsible for analysis and design of the
software
 Coder/Implementer: Programmer. Help in detecting defects that
could lead to coding errors in Implementation phase
 Tester: Leader of the testing team who focuses on identification of
design errors
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Participants of Peer Review
•
Specialized Professionals - Walkthrough
 Standard Enforcer: Specializes in development standards and
procedures. Main job is to detect deviations.
 Maintenance Expert: Focuses on maintainability, flexibility and
testability issues. Also reviews the documentation for correctness
and completeness.
 User Representative: Looks at the system from the user’s point of
view. If external user is not available, a member plays the role of a
user.
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Participants of Peer Review
•
Team Assignments
 Presenter: In Inspections, it is usually the coder as he understands
the system’s design logic. In Walkthroughs, it is the author.
 Scribe: The team leader is often the scribe – person who takes notes
during the review sessions.
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Walkthroughs
Maint.
Expert
User
Rep
Author
(Presenter)
Inspections
Standards
Enforcer
Moderator (Scribe)
Author
Participants in Peer Review
Coordinator (Scribe)
Designer
Coder
(Presenter)
Tester
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Preparations for a Peer Review session
•
Review Leader Preparations
 Determine which sections need to be reviewed
 Most difficult and complex sections
 Critical sections
 Sections likely to have defects
 To select team members
 Schedule the Peer Review sessions
 Limit a review session for 2 hours
 Max. two sessions per day can be held
 Distribute the document to the team members
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Preparations for a Peer Review session
•
Review Team Preparations
 Inspection Team Members
 Read the document and list their comments
 Author can provide an overview session if the material in unclear
 Walkthrough Team Members
 Briefly read the documents
 No need to prepare comments in advance
•
Specialized Review Checklists can be used for common type of
development documents
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The Peer Review Session
•
Session Process
 Presenter reads the document and explains it in his own words
 Comments made by the review team
 Scribe notes down all the defects identified
 Location, description, type and character of defects
 Estimate the severity of defect
•
Session Documentation
 Inspection
 Inspection session findings report – List all the defects identified and
suggested corrections
 Inspection session summary report – Written by the inspection leader
detailing about the session findings and resources used.
 Walkthroughs – Only the walkthrough session finding report is
distributed to the development team.
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Post-Review: The DR Report
•
Walkthrough
 No follow-up done post the session
•
Inspections
 Effective correction of the errors identified.
 Submission of the inspection report to the Internal Corrective
Action Board (CAB) for analysis.
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Efficiency of Peer Review
 Peer review detection efficiency: Average hours worked per
defect detected.
 Peer review defect detection density: Average number of defects
detected per page of the design document
 Internal peer review effectiveness: Percentage of defects
detected by peer review as percentage of total defects detected by the
developer.
Important Note: Practice the calculation on pg. 167
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Walkthroughs
Preparation
Preparation
Overview Meeting
Detail review of
document
Inspection session
Brief Overview
Reading
Walkthrough
Session
Inspection session report & summary report
Correction & Rework
Follow-up of
Correction
Process of Peer Review
Inspections
Walkthrough session report
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Peer Review Coverage
•
Not everything is reviewed
•
5-15% of document pages coverage
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Comparison of Reviews
Property
Formal DR
Inspection
Detect errors
Identify risks
Approve
document
Detect errors
Identify
deviations
Knowledge
exchange
Knowledge
exchange
Support
corrections
Knowledge
exchange
Review
Leader
Chief S/W Eng.
Moderator
Coordinator
Participants
Top-level staff
Cust. Rep.
Peers
Peers
Yes
Yes
Yes
-
Designer
Coder
Tester
Std. Enforcer
Maint. Expert
User Rep.
Direct
Objective
Indirect
Objective
Project
Leader
Specialized
Professionals
Walkthrough
Detect errors
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Comparison of Reviews
Property
Formal DR
Inspection
Walkthrough
No
Yes
Yes
Yes thorough
Yes - thorough
Yes - brief
Review Session
Yes
Yes
Yes
Follow-up
Yes
Yes
No
Formal Training
No
Yes
No
Use checklist
No
Yes
No
Error data
collection
Not required
Required
Not required
Review Doc
Formal DR
report
Findings report
Summary
report
Findings report
Overview
Meetings
Participant
Preparation
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