Medical devices verification

Software validation is not separately defined in the quality system regulation. The FDA considers software validation to be the confirmation by examination and provision of objective evidence that software specifications conform to user needs and intended uses, and that the particular requirements implemented through software can be consistently fulfilled [14]. Software validations have special concerns on software installation, implementation, and utilization. A software validation consists in several tests, inspections, and verifications performed to assure the adequate installation and use of software and that the tasks performed meet all the specifications defined. Software validations must be performed under the environmental conditions to which software will be submitted. This is particularly important in medical devices that are used under special conditions, such as close to or inside the human body. 

The medical devices for category 3 in Table 1 are constituted (assembled) at the user site. Method verification for constitution should be one of the key factors, as well as qualification and validation in the manufacture of components (parts). Nuclear magnetic resonance spectroscopy (NMR) is included in this category. 

Validation in quality systems includes establishment of procedures on how to qualify the equipment and machinery, how to verify the design of products, how to verify the process designed, how to verify the achievement of production procedures, how to validate the process developed, and how to validate the methods for measurement and assay. Validation also requires verification of specifications or acceptance criteria of in-process parameters relating to both raw materials and intermediate (in-process product) and finished products, and verification of acceptance criteria for in-process parameters relating to operating conditions of machinery and equipment. Further, when the medical device is assembled at the user s site, validation includes establishing procedures of how to verify assembly. 

Acceptance criteria must be key to achieve appropriate qualification, verification, and individual validation. Acceptance criteria may be consist of various specifications of intermediate and finished products for medical devices. Acceptance criteria also may control parameters for operation of processing equipment and utilities used. 

For medical devices, there is a phenomenon recognized as feature creep , in which the specifications for the design features of a device begin to drift toward a specification limit because inadequate design reviews, output verification and change control. This same sort of variability occurs with... 

Medical Many types of medical devices rely on adhesives for assembly. Medical device manufacturing requires that the final product exhibit maximum reliability and performance under many conditions that are not common in other industries. As a result, manufacturers of medical devices require significant testing and verification prior to choosing an adhesive. The standards and regulations in this industry are much different from those of other industries. The nature of the medical device market also dictates that the adhesive be economical and amenable to high-volume manufacturing methods. 

The aim of this chapter is to describe the general framework for conducting good clinical practices (GCP)-compliant clinical research. As it is difficult to cover this broad topic in such a short chapter, the authors will focus on those areas that are most discussed, most problematic and most critical to achieving a GCP-compliant clinical study. Thus, there is particular emphasis on ethical issues, source data verification and data integrity, monitoring and safety review, and study medication/device management. 

Reich, R., Sharpe, D., and Anderson, H Accelerated Aging of Packages Consideration, Suggestions, and Use in Expiration Date Verification, Medical Device and Diagnostics Industry, March 1988, pp. 34-38. 

Abstract A recent standard for medical device software lifecycle processes, ISO/IEC 62304 (ISO 2006), assumes and specifies a software safety classification scheme, where docmnentation, verification and validation tasks to be carried out depend on the safety classification. This means that a risk-driven approach has become an accepted standard for medical devices. 

To be able to certify that software can be commercialized because it is safe and fulfils its mission for public health, an inspector needs to know what the software does, that it works properly and that it does not imply risks. Validation of safety is a broad concept for medical devices in software speak it means the assurance that the process of software design, construction and verification is planned and controlled. 

There are more than 900 standards in the medical devices domain. By law, and in order to receive the respective certifications required, the devices must adhere to all applicable standards. Safety standards are very high to ensure patient safety even in the presence of a fault. Therefore companies in the medical devices domain have to spend considerable effort to fulfill the required level of safety. In addition, every company strives to improve the safety of their devices even further and thus has some internal standards with which the devices must comply. In some cases, formal verification is considered but it is currently only applied for small parts of the system. In most cases, though, formal verification is not considered applicable due to the very high complexity the products have today. Some parts of the devices may require different amounts of verification effort. Parts considered especially safety-relevant are tested very thoroughly in either case. 

Each requirement for a medical device has to be written in such a way that it is testable. At the end of the development cycle, verification and validation of the product has to be performed. This is meant to guarantee that the product developed is the product desired by the user. The verification step is simplified if the requirement specification is written in a form that every requirement is testable. Therefore, the test department is included in the process of writing the requirements. In generating a model and in writing the requirements in a testable way, the test department can plan and develop tests for the system verification phase. Having the tests be developed in parallel to the system itself saves valuable time and leads to shorter time to market. The verification phase is usually followed by a validation phase. This validation phase is somewhat comparable to a beta test phase common with software products. The devices are given to a defined number of users for validation. Of course, this phase should not lead to requirement changes. 

The verification/validation activities must attempt assertively to uncover issues rather than seeking to merely demonstrate that the medical device meets the DIR. 

Every requirement in the DIR must be verified even if the requirement is carried over from a previous device. Whenever possible, perform step stress testing to failure, this is used to ensure there is adequate design margin in the device. This discussion addresses primarily the final medical device. However, the expeeta-tion is that similar verification activities will also be carried out for all critical subsystem and custom component specifications. 

Design input is the most important element in the development of a successful medical device. Design input forms the basis of all development activities, it is also the standard for which all verification and validation activities are based. Unfortunately, organizations often short-cut this part of the project because they... 

Making medical devices safer involves a constructive dialogue among stakeholders (manufacturers, regulators, clinicians), and a verification approach based on... 

The model-based approach incorporates several concepts promoted by medical device regulators and which should be directly applicable to the development of real medical devices. For instance, in [21] and [9], the FDA Office of Science and Engineering Lab (OSEL) engineers have promoted the formalisation of safety requirements as generic models that can be used for verification of real devices. 

Masci, P., Ayoub, A., Curzon, P., Harrison, M.D., Lee, 1., Thimbleby, H. Verification of interactive software for medical devices PGA infusion pumps and FDA regulation as an example. In EICS 2013. ACM Digital Library (2013)... 

These electronic devices provide instant access to patient information. Caregivers can electronically assess, monitor, and chart patient care electronically. Some hospitals use coordinated systems that address patient care, medication verification, and computerized provider order entry. 

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