Valeria,
Great question and one which will never receive a straight answer, because every device is different, or there would be no market for the new device.
To assure a logical sequence is planned for upcoming performance and conformance tests there are many engineering, clinical, and business factors to balance. As a regulatory member of the cross-functional team it is essential that you become familiar with the technical standards the company is planning to assert in the market clearance or IDE submission to the agency. However, demonstrating conformance to standards is necessary, but not sufficient. The regulatory challenge is communicating that the entire portfolio of safety and effectiveness testing is sufficient to mitigate the risk of the authorization being requested. So, start at the top, by requesting that the cross-functional team build a comprehensive top down (from the perspective of clinical use) and bottoms up (from the perspective of product design and build) risk analysis of the device. Those risks that are highest should receive the most attention in testing.
Once an appropriate suite of qualification tests are outlined, the sequence of the testing will take into account the duration of the test (long tests may be started first), the cost of the tests (very expensive tests may wait until more basic tests have demonstrated success), and any required input to a test (test protocol may need to be reviewed by the agency before being executed). There can be some very important economies gained by creative sequencing of tests such as using one group of devices for multiple tests. However, your engineering team members need to be very confident that one set does not interfere with the results of the next. The condition of the devices at the time of the test is very important, many devices need to be sterilized in their packages before initiating an expensive test.
Long duration tests are the most expensive, because they delay the next step in the business plan. A 600,000,000 cycle mechanical test, for example, under optimal conditions may take 6 months to execute and may reveal that the product needs redesign. Using simulation to analyze the design before undertaking such a test, may save trial and error.
Be a team player, the answers are within.
- Kate
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Katharine Stohlman RAC
Waltham MA
United States
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Original Message:
Sent: 12-05-2012 10:56
From: Valeria Sena-Weltin
Subject: Sequence for mechanical tests
Good morning,
I've been reading on mechanical testing for medical devices and in several occasions the sequence in which the tests are done is mentioned, however, no one list the correct sequence.
Can anyone provide me any direction in this topic?
Thank you,
Valeria
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Valeria Sena-Weltin RAC
New Market MD
United States
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