Change control within quality management systems (QMS) and information technology (IT) systems is a formal process used to ensure that changes to a product or system are introduced in a controlled and coordinated manner. It reduces the possibility that unnecessary changes will be introduced to a system without forethought, introducing faults into the system or undoing changes made by other users of software. The goals of a change control procedure usually include minimal disruption to services, reduction in back-out activities, and cost-effective utilization of resources involved in implementing change.
Change control is currently used in various products and systems. For IT systems it is a major aspect of the broader discipline of change management. Typical examples from the computer and network environments are patches to software products, installation of new operating systems, upgrades to network routing tables, or changes to the electrical power systems supporting such infrastructure.
Certain portions of the Information Technology Infrastructure Library cover change control.
Certain experts describe change control as a set of six steps[who?]:
The client initiates change by making a formal request for something to be changed. The change control team then records and categorizes that request. This categorization would include estimates of importance, impact, and complexity.
The impact assessor or assessors then make their risk analysis typically by answering a set of questions concerning risk, both to the business and to the process, and follow this by making a judgment on who should carry out the change. If the change requires more than one type of assessment, the head of the change control team will consolidate these. Everyone with a stake in the change then must meet to determine whether there is a business or technical justification for the change. The change is then sent to the delivery team for planning.
Management will assign the change to a specific delivery team, usually one with the specific role of carrying out this particular type of change. The team's first job is to plan the change in detail as well as construct a regression plan in case the change needs to be backed out.
If all stakeholders agree with the plan, the delivery team will build the solution, which will then be tested. They will then seek approval and request a time and date to carry out the implementation phase.
All stakeholders must agree to a time, date and cost of implementation. Following implementation, it is usual to carry out a post-implementation review which would take place at another stakeholder meeting.
In a Good Manufacturing Practice regulated industry, the topic is frequently encountered by its users. Various industrial guidances and commentaries are available for people to comprehend this concept. As a common practice, the activity is usually directed by one or more SOPs. From the information technology perspective for clinical trials, it has been guided by another U.S. Food and Drug Administration document.