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  • 1.  Best way to describe the difference between DMR and DHR

    This message was posted by a user wishing to remain anonymous
    Posted 16 days ago
    This message was posted by a user wishing to remain anonymous

    Trying to explain the difference between DMR (§ 820.181) and DHF (§ 820.30 j) to a lay person. 



  • 2.  RE: Best way to describe the difference between DMR and DHR

    Posted 15 days ago

    Alright, let's simplify this by imagining we're talking about building a custom car, a process not too different from developing a medical device in terms of documentation and regulation.

    DHF (Design History File) - § 820.30(j): Think of the DHF as the complete storybook of your custom car project. From the moment you sketched your first design on a napkin, through every adjustment and decision you made about its engine, paint color, and interior design, to the final blueprint you decided on. This file contains all the records and documents that describe the design history of the car. It's like a diary that captures your journey from concept to the final design, showing all the tests you ran to ensure the design was safe and met your requirements. If someone asked, "How did you come up with this design?" or "Why did you choose this specific engine?", you could point to the DHF for answers.

    DMR (Device Master Record) - § 820.181: Now, imagine the DMR as the ultimate recipe or instruction manual for building your custom car. It includes detailed specifications for materials (what kind of metal for the body, what type of leather for the seats), parts lists, assembly instructions, and quality assurance procedures. If the DHF is the story of how the car's design evolved, the DMR is the guide to replicating the final car exactly as it was intended. If someone else wanted to build another car just like yours, they would follow the DMR to ensure it matches the original in every way.

    In essence, the DHF is the "why" and "how" of the design process, capturing the evolution of the device's design, while the DMR is the "what" and "with what" that specifies everything needed to manufacture the device consistently. Both are crucial in the medical device industry for ensuring products are designed and produced safely, effectively, and to the highest standards.



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    Jonas Bundgaard MSc
    Sr. Regulatory Affairs Consultant
    NorMed Consulting
    Copenhagen
    Denmark
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  • 3.  RE: Best way to describe the difference between DMR and DHR

    Posted 15 days ago

    Hi Anon,

    Jonas provided a great explanation - completely agree on the why/how and what approach.  A simple explanation I use often in training is:

    • Design History File (DHF) - known as Design and Development Records from ISO 13485: This is how you created your recipe to make a cake.  During "development" you decided to make a carrot cake versus a chocolate cake and then the carrot cake has 3 carrots instead of 1 or 100 mL of pineapple instead of 50 mL.  These are the Inputs into the recipe.
    • Device Master Record (DMR) - known as Medical Device File (MDF) from ISO 13485: This is then the recipe for the Carrot Cake.  You could also have a DMR/Recipe for Chocolate Cake and one for Vanilla Cake.  This is all the ingredients and steps which are needed to make the cake.  This is the Output which is the recipe itself.
    • Device History Record (DHR) - known as batch or lot records from ISO 13485: This is then the cake itself.  The recipe would have little entries/checkmarks showing you put 3 carrots, 300g flour, 100 mL pineapple, 10 g cinnamon, etc., which would be recorded.  If it was too sweet then the next recipe "record" would be 150g sugar instead of 200g.

    (And wonder about pineapple in carrot cake ... makes it nice and moist !)



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    Richard Vincins ASQ-CQA, MTOPRA, RAC
    Principal Strategy Consultant
    NAMSA
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  • 4.  RE: Best way to describe the difference between DMR and DHR

    This message was posted by a user wishing to remain anonymous
    Posted 15 days ago
    This message was posted by a user wishing to remain anonymous

    The DMR is the recipe or practical steps for making the product.  The DHF is the journal of how and why the product design came to be.




  • 5.  RE: Best way to describe the difference between DMR and DHR

    Posted 15 days ago

    Hi Anon

    Simply put for the lay person,  the DHF (Design History File) is the records of all the planning, design and testing you performed to  come up with a medical device product that meets a user need and is robust, safe and effective.    You experimented, refined, documented and came up with the consistent recipe (the DMR- the Device Master Record) for repeatedly  successfully making a device, or a batch or lot of devices. (Cookie recipe and manufacturing process).

    The DHR (Device History Record) is the records of how you made, tested, packaged, , labeled, released) each batch or lot of the device (e.g., the cookies). Yep, this has to be documented too.

    A baking analogy is what I use for true newbies.  It is actually easier in pharma I think because the terminology is : 

    1) Pharmaceutical development report (summary report describing and referencing development activities throughout the whole project)

    2) Master Batch Record: the "recipe"

    3) Production Batch Record : " what was actually done to make the batch"

    Good luck!



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    Ginger Cantor, MBA, RAC
    Founder/Principal Consultant
    Centaur Consulting LLC
    River Falls, Wisconsin 54022 USA
    715-307-1850
    centaurconsultingllc@gmail.com
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