Inspection
Inspection is the most formal review type. The document under inspection is prepared and checked thoroughly by the reviewers before the meeting, comparing the work product with its sources and other referenced documents, and using rules and checklists. In the inspection meeting the defects found are logged and any discussion is postponed until the discussion phase. This makes the inspection meeting a very efficient meeting.
The reason for carrying out inspections can be explained by using Weinberg’s concept of egoless engineering [Weinberg, 1971]. Weinberg refers to the human tendency to self-justify actions. Since we tend not to see evidence that conflicts with our strong beliefs, our ability to find errors in our own work is impaired. Because of this tendency, many engineering organizations have established independent test groups that specialize in finding defects. Similar principles have led to the introduction of inspections and reviews in general.
Depending on the organization and the objectives of a project, inspections can be balanced to serve a number of goals. For example, if the time to market is extremely important, the emphasis in inspections will be on efficiency. In a safety-critical market, the focus will be on effectiveness.
The generally accepted goals of inspection are to:
- help the author to improve the quality of the document under inspection;
- remove defects efficiently, as early as possible;
- improve product quality, by producing documents with a higher level of quality;
- create a common understanding by exchanging information among the inspection participants;
- train new employees in the organization’s development process;
- learn from defects found and improve processes in order to prevent recurrence of similar defects;
- sample a few pages or sections from a larger document in order to measure the typical quality of the document, leading to improved work by individuals in the future, and to process improvements.
Key characteristics of an inspection are:
- It is usually led by a trained moderator (certainly not by the author).
- It uses defined roles during the process.
- It involves peers to examine the product.
- Rules and checklists are used during the preparation phase.
- A separate preparation is carried out during which the product is examined and the defects are found.
- The defects found are documented in a logging list or issue log.
- A formal follow-up is carried out by the moderator applying exit criteria.
- Optionally, a causal analysis step is introduced to address process improvement issues and learn from the defects found.
- Metrics are gathered and analyzed to optimize the process.
3.2.4 Success factors for reviews
Implementing (formal) reviews is not easy as there is no one way to success and there are numerous ways to fail. The next list contains a number of critical success factors that improve the chances of success when implementing reviews.
It aims to answer the question, “How do you start (formal) reviews?”.
Find a “champion”
A champion is needed, one who will lead the process on a project or organizational level. They need expertise, enthusiasm and a practical mindset in order to guide moderators and participants. The authority of this champion should be clear to the entire organization. Management support is also essential for success. They should, amongst other things, incorporate adequate time for review activities in project schedules.
Pick things that really count
Select the documents for review that are most important in a project. Reviewing highly critical, upstream documents like requirements and architecture will most certainly show the benefits of the review process to the project.
These invested review hours will have a clear and high return on investment. In addition make sure each review has a clear objective and the correct type of review is selected that matches the defined objective. Don’t try and review everything by inspection; fit the review to the risk associated with the document. Some documents may only warrant an informal review and others will repay using inspection. Of course it is also of utmost importance that the right people are involved.
Explicitly plan and track review activities
To ensure that reviews become part of the day-to-day activities, the hours to be spent should be made visible within each project plan. The engineers involved are prompted to schedule time for preparation and, very importantly, rework. Tracking these hours will improve planning of the next review. As stated earlier, management plays an important part in planning of review activities.
Train participants
It is important that training is provided in review techniques, especially the more formal techniques, such as inspection. Otherwise the process is likely to be impeded by those who don’t understand the process and the reasoning behind it. Special training should be provided to the moderators to prepare them for their critical role in the review process.
Manage people issues
Reviews are about evaluating someone’s document. Some reviews tend to get too personal when they are not well managed by the moderator. People issues and psychological aspects should be dealt with by the moderator and should be part of the review training, thus making the review a positive experience for the author. During the review, defects should be welcomed and expressed objectively.
Follow the rules but keep it simple
Follow all the formal rules until you know why and how to modify them, but make the process only as formal as the project culture or maturity level allows. Do not become too theoretical or too detailed. Checklists and roles are recommended to increase the effectiveness of defect identification.
Continuously improve process and tools
Continuous improvement of process and supporting tools (e.g., checklists), based upon the ideas of participants, ensures the motivation of the engineers involved. Motivation is the key to a successful change process. There should also be an emphasis, in addition to defect finding on learning and process improvement.
Report results
Report quantified results and benefits to all those involved as soon as possible, and discuss the consequences of defects if they had not been found this early. Costs should of course be tracked, but benefits, especially when problems don’t occur in the future, should be made visible by quantifying the benefits as well as the costs.
Just do it!
The process is simple but not easy. Each step of the process is clear, but experience is needed to execute them correctly. So, try to get experienced people to observe and help where possible. But most importantly, start doing reviews and start learning from every review.
