User requirement specifications computer validation

A computer system is composed of software and hardware, equipment, a processor, and a user, and it is used to execute a specific procedure. Regardless of whether the computer system is developed in-house or by a contractor or purchased off the shelf, establishing documented end-user requirements is extremely important for computer systems validation. Without first establishing end-user needs and intended use, it is virtually impossible to confirm that the system can consistently meet them. Once established, it should obtain evidence that the computer system implements those needs correctly and that they are traceable to system design requirements and specifications. It is important that the end-user requirements specifications take into account predicate rules [12]. 

Qualification of equipment and validation of computer systems are not one-time events. They start with the definition of the product or project and setting user requirement specifications and cover the vendor selection process, installation, initial operation, ongoing use, and change control. 

The information contained in User Requirements Specifications is often used to help determine the basic approach to validation to be taken for individual projects. Guidance on the scope of validation required for different types of computer systems is defined at the beginning of this chapter. A rationale must always be given supporting any validation decisions made during a validation project in the form of a separate document or included within the Validation Plan. 

User Requirements Specification X X X X for exact replicas of a computer system the Validation Plan canbeproceduralized reference may be made to the Project QuaUty Plans and Supplier Quality Plans if they are separate documents Typically a single document covering whole system... 

Computer systems supplied by third parties (often known as system integrators) to specific user requirements should be validated entirely prospectively along the same lines that pharmaceutical and healthcare companies take for in-house developments. This, of course, requires that validation requirements are clearly identified and understood by the supplier at the outset of a project. 

The performance of the complete system should be validated against the User Requirements Specifications. The system combines the instrument hardware, computer hardware and software, and the analytical method. In chromatography, it also includes a column... 

For DCS systems, the process and computer validation usually progress in parallel, converging at the Operational Qualification stage. Often there is an overall validation plan for the process with a separate validation plan for the process control system as a subset of this. The starting point for both plans is often a common User Requirement Specification for the facility. 

ISO/IEC EDIS 17025—General Requirements for the Competence of Testing and Calibration Laboratories 1999. Segalstad, S.H. The user requirements specification—the most important tool in the validation. Sci. Comput. Instr. 2000 (Fall), 24-25. 

The most important factors for the entire process of equipment qualification and computer system validation in analytical laboratories are proper planning, execution of qualification according to the plan, and documentation of the results. The process should start with the definition of the analytical technique and the development of user requirement and functional specifications. For computer systems, a formal vendor assessment should be made. This can be done through checklists and vendor documentation with internal and/or external references. For very complex systems, it should go through a vendor audit. 

The main business reasons to validate computer systems are to demonstrate conformance with the system requirements specification, to increase acceptance of the systems by end-users, and to avoid high maintenance costs. Regarding maintenance costs, Figure 2-2 depicts the relative cost in 1976 of repairing software. At present, the proportions are similar. The longer a defect is uncovered, the more expensive it is to repair. 

Abstract Existing software and computer systems in laboratories require retrospective evaluation and validation if their initial validation was not formally documented. The key steps in this process are similar to those for the validation of new software and systems user requirements and system specification, formal qualification, and procedures to ensure ongoing performance during routine operation. 

All software and computer systems used in accredited and GLP- and GMP-regulated analytical laboratories for the generation and analysis of critical data should be retrospectively evaluated and formally validated. As a first step, the user should list all systems in the laboratory, assess the need for validation for each system and develop an implementation plan. For validation of individual systems, the validation plan should describe user requirements and specific validation steps. It should also list the person or persons responsible for each step as well as the criteria that must be met to achieve validated status. 

For computer systems that do not require formal validation, at a minimum, user acceptance testing should be performed. This User Acceptance Testing should be outlined in a facility SOP, where the system is tested and assured to perform in the desired function effectively. The User Acceptance should be documented, and the system should be released for specific uses. 

Computer systems validation, implied in 21 CFR Part 211.68, established in 21 CFR Part 11.10(a), and defined in the recent draft FDA guideline,4 is one of the most important requirements applicable to computer systems performing regulated operations. Computer systems validation is the confirmation (by examination and the provision of objective evidence) that computer system specifications conform to user needs and intended uses, and that all requirements can be consistently fulfilled. It involves establishing that the computer system conforms to the user, regulatory, safety, and intended functional requirements. 

Even though the definitions look similar, there is a distinct difference. While verification is of general nature, validation refers to specific intended use . In this sense a computer system that is developed for multiple users with multiple applications is verified rather that validated at the vendor s site. When the system is installed at the user s site for a specific task and the system is tested to meet the previously specified requirements, this process is defined as validation. If the system is intended to be used for different applications and more generic tests are done in the sense of EN ISO 8402 1995, this process again is called verification. 

An important attribute of an equation of state for engineering applications is relative simplicity, resulting in minimal computation time for calculation of the necessary properties. Although the use of developed software has become common in engineering applications, situations that require user specific software are still frequent. If requirements of either precise estimate or demands with regard to the range of validity can be relaxed, then equations of state with fewer terms for specified levels of precision may be developed to reduee eom-putation times. 

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