Medical device design validation

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... 

Software Validation Authorities are demanding rules in order to outline the software validation principles used in medical device software or the validation of software used to design, develop, or manufacture medical devices. 

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. 

The design specification describes, in a narrative and/or pictorial form, how the software will accomplish the software requirements and the interactions with the hardware to accomplish various functions of the device s design. 11 The most recent FDA validation guidance,12 which is exclusively applicable to medical devices, provides comprehensive information on the implementation of applicable software validation regulations to medical device computer systems performing regulated operations. 

Computer systems validation personnel must also deal with design errors. A program that perfectly meets a lousy specification is a lousy program. Specifically for medical devices, books on software reliability tend to set aside the user interface issue, and treat it as the sole province of the human factor analyst. The reliability of a system is determined by how all its various parts, including the people who use it, work together. 

Medical devices used to take chnical trial measurements must comply with medical device regulatory requirements. These cover design controls and software validation.Another case study in this book deals with medical device validation (see Chapter 40 Case Study 22). 

The following is an excellent example of a typical designed experiment performed early in the development process (i.e., long before process validation studies). It is based on an actual study performed at a medical device manufacturing plant. 

This title demonstrates how designed experiments are the most scientific, efficient, and cost effective method of data collection for validation. Intended as a learn-by example guide. Pharmaceutical and Medical Device Validation by Experimental Design demonstrates why designed experiments are the most logical and rational approach to use, using realistic case studies, illustrations, and where appropriate, step-by-step protocols and procedures. 

Pharmaceutical and medical device validation by experimental design / edited by Lynn D. Torbeck. 

During the design and development of a medical device, numerous U.S. and international standards must he met to validate the device s performance, material used, and safety. 

ISO 14971 has been adopted by the European Committee for Standardization as EN ISO 14971 2012 [6]. Importantly it is one of the harmonised standards which manufacturers are obliged to comply with if they wish to certify their product as a CE Marked medical device (including in vitro diagnostic devices). Similarly in the US, the 21 code of federal regulations requires risk management to be undertaken as part of design validation (820.30 (g)). ISO 14971 is a Recognised Consensus Standard which the FDA expects manufacturers to comply with to meet this requirement. 

ISO 11607 addr ses the package system validation in three phases, or clauses. Clause 4 specifies the basic attributes required for a wide range of materials as they combine and interact with various medical devices, packaging designs, sterilization methods, and distribution modes. Clause 5 defiites the framework of activities to qualify the processes used to make and assemble the final package... 

Nolan, Patrick J., Medical Device Package Design A Protocol for Sterile Package Integrity Validation, Jl/ //ca/ Device and Diagnostics Industry, November 1995. 

In this section, the sterilization and biocompatibility of SMPs are discussed jointly. All proposed SMP medical devices evenmally have to be validated with a designated sterilization method before they can be used clinically. The method of sterilization can influence the biocompatibility and performance of a device [104, 105], Subsequently, sterilization can also alter the thermomechanical properties of the polymer, which directly influence shape-memory properties such as shape storage (fixity) and recovery [106]. Currently, there are three types of sterilization methods including heat, radiation, and chemical techniques. 

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. 

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