Design ReviewsPeer 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.

3

• 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.

Inspections

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• 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

Participants of Peer Review

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• 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.

Participants of Peer Review

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• 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

Participants of Peer Review

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• 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.

Participants of Peer Review

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• 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.

Participants of Peer Review

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Part

icip

ants

in P

eer

Revi

ew

10

Inspections

Walkthroughs

Coder (Presenter)

Author

Designer

Tester

Moderator (Scribe)

Author(Presenter)

Maint.Expert

UserRep

StandardsEnforcer

Coordinator (Scribe)

• 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

Preparations for a Peer Review session

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• 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

Preparations for a Peer Review session

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• 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.

The Peer Review Session

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• 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.

Post-Review: The DR Report

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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.

Efficiency of Peer Review

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Important Note: Practice the calculation on pg. 167

Proce

ss o

f Pe

er

Revi

ew

16

Inspections Walkthroughs

Inspection session report & summary report

Preparation

Overview Meeting

Detail review of document

Inspection session

Correction & Re-work

Follow-up of Correction

Preparation

Brief Overview Reading

Walkthrough Session

Walkthrough session report

• Not everything is reviewed

• 5-15% of document pages coverage

Peer Review Coverage

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Comparison of Reviews

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Property Formal DR Inspection Walkthrough

Direct Objective

Detect errorsIdentify risks

Approve document

Detect errorsIdentify

deviations

Detect errors

Indirect Objective

Knowledge exchange

Knowledge exchangeSupport

corrections

Knowledge exchange

Review Leader Chief S/W Eng. Moderator Coordinator

Participants Top-level staffCust. Rep. Peers Peers

Project Leader Yes Yes Yes

Specialized Professionals

-Designer

CoderTester

Std. EnforcerMaint. Expert

User Rep.

Comparison of Reviews

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Property Formal DR Inspection Walkthrough

Overview Meetings No Yes Yes

Participant Preparation

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 reportSummary

reportFindings report