8 Part 8: Annex

8.1 Method References

8.1.13 Review

Usage

Evaluating Document, Preparing Evaluation Specification Document, Preparing Software Implementation, Integration and Evaluation Concept, Integrating into Logistic Support Documentation

Reference

FW90, Bal00

Purpose

A Review is a scheduled, critical, systematic and documented content check of the results of the work at the end of defined work steps. The Review is characterized by a defined approach that is put down in writing. In the review testing is performed on the basis of defined specifications (e. g. reference documents, evaluation criteria). In the test tools (such as forms and checklists) are used, and the results of the review are evaluated and documented in a protocol. CMMI® calls for so-called Peer Reviews. Those are reviews performed by peers, i. e. knowledgeable colleagues.

The goals of the Reviews are:

• Checking results on the basis of objective evaluation criteria,
• Detecting and eliminating faults in the results of the work at an early stage,
• Ensuring compliance with guidelines, standards and other specifications,
• Avoiding that work performed in earlier phases is repeated,
• Minimizing the costs of the elimination of faults,
• Obtaining »Measurement Data Types for the evaluation of the quality of results and the process,
• Disclosing deficiencies in the development process,
• Gaining experience so that in the future faults can be avoided.

The Review starts with preliminary work that includes an introductory meeting (depending on the method) and the preparation of the review meeting (e. g. selection of the date and the location). Then the Review is performed in accordance with a previously defined procedure. The faults and suggestions for improvement for the review object (e. g. document, code, drawing or process) that were documented during the review are worked over by the author of the review object. Then the review object may be released.

The following requirements apply to the review procedures that are to be used:

• The schedule, the individual steps and the »Roles and their tasks have been defined and described.
• All steps that have to be performed have been planned and the persons in charge and the evaluation criteria have been determined.
• The results of the Review are recorded, the fault data and expenditures are documented and analyzed.

There are some basic review procedures that vary in their structure and schedule and in the roles (including tasks) that are used:

• In the "Comment Technique" procedure (for example an opinion) the review is performed separately by the »Inspectors; there is no meeting.
• In "Meeting Technique" procedures, such as a walkthrough, peer review or one-to-one talk, the faults found during the preparation are discussed in the meeting.
• In Inspections, such as intensive inspection of code or documents, the contents of the objects to be tested are systematically discussed.
• In "Combined Procedures" different procedures from written comments and the review meeting are combined.

Review Methods:

Inspection or Walkthrough

The walkthrough is a formalized review technique with defined approach and role allocation in the review meeting. The objective of the review procedures inspection and walkthrough is to identify existing faults or fault-prone situations and to measure quality. The object of the review procedure is the source text of the program (in connection with the specification), the document or the drawing.

A walkthrough is recommended for objects of high complexity or with a high fault density. The number of persons participating in the review may be between three and seven. A larger number of participants usually requires additional efforts that are not matched by an additional benefit in the form of a larger number of detected faults; also tight moderation of a meeting with eight or more participants is no longer possible.

A walkthrough or an inspection of a document, a code or a drawing is performed mostly in a team of about four persons. In addition to the developer, this team includes one moderator and some experts. The developer explains the program logic statement by statement or the document sentence by sentence. The team members ask questions and identify faults. The recommended duration of a meeting is approximately two hours.

One-to-One Talk

The one-to-one talk is a special form of the walkthrough; by limiting the participation to only two persons the effort required for the review is to be kept small. However, to ensure an intensive review and that if possible all faults are found, in this technique the functions to be performed and the sequential steps are specified in concrete terms and on top of that, with the reader, a special function is provided. Because of the smaller number of persons, however, it is possible that important experience and know-how of those staff members who are not involved may be lost.

Combined Procedures

In those cases in which as many participants as possible are to be involved in the review, which, however, would exceed the planned maximum number of participants in one meeting, a combination of two review techniques is practical. This is for example the case if the review object has to be considered from many different points of view or if it affects a large number of authorities.

The combination includes, firstly, written comments provided by staff members who cannot or are not to take part in the meeting in connection with a walkthrough and, secondly, a walkthrough. In a first phase the review object is checked by all possible participants in order to seek as many comments as possible. This is followed by a walkthrough in which only selected staff members (for example those who are primarily affected by the review object) or those staff members who are available at the time of the meeting will take part.