Guidelines for complying with ISO 13485 regarding validation and computerized system validation

This basically depends on the type of the medical device that you have and regulations that you need/want to be in compliance with.

In general, in ISO 9001:2015 validation is defined as "confirmation, through the provision of objective evidence, that the requirements for a specific intended use or application have been fulfilled". As for medical devices, validation involves an "assessment by objective means of whether the specified users are enabled to achieve the specified goals (intended purpose) within the specified context of use".  

Computer System Validation (CSV) is a documented process of assuring that a computerized system does exactly what it is designed to do. Requirements for validation of computer systems can be found in:

• FDA 21 CFR part 820.70
• FDA 21 CFR part 11.10
• FDA 21 CFR part 11
• FDA Guidance Document regarding Software Validation
• ISO 13485, in chapters 4.1.6, 7.5.2.1 and 8.2.3
• Good manufacturing practice directives
• Guidance to achieve compliant computerized systems (GAMP 5), e.g. regarding the "risk-based approach of testing GxP systems"

For more information on validation, please see following articles:

• Using ISO 13485 to manage process validation in the medical device manufacturing industry https://advisera.com/13485academy/blog/2017/09/07/using-iso-13485-to-manage-process-validation-in-the-medical-device-manufacturing-industry/
• How to establish process validation in the QMS https://advisera.com/9001academy/blog/2017/01/31/how-to-establish-process-validation-in-the-qms/