Awards & Accreditation

Executive Directors

Lorin Gresser

Chief Executive Officer
Lorin founded Dem Dx in 2015 after graduating from medical school and has been the CEO of Dem Dx ever since. As well as her medical degree from King's College London she has a MA in Natural Sciences from Cambridge University and an MBA from Harvard University.

Steve Varley

Chief Technical Officer
Steve has over 30 years experience in open systems software design, including 10+ years in mobile app development. Steve holds a BA in Computing Science from Teesside University.

Non-executive Directors

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Karen Bach

Chair of the Board
Karen joined Dem Dx as Chair in 2021. She brings 30 years of experience in growing, international businesses with a focus on scale-ups particularly in health tech and media tech. Karen joined Dem Dx because she is blown away by the diagnostics tool and the productivity it delivers to resource-constrained health care organisations.
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Tracy Sambrook

Tracy joined DemDx as an NED in 2021. She brings 20 years of finance experience, scaling and raising funding for growth-stage businesses across the tech sector. Tracy joined Dem Dx because of Dem Dx's capability to deliver significant and much needed transformation to frontline healthcare, offering an opportunity to improve healthcare delivery in both developed and developing healthcare environments.

Tyhoa Kobler

Tyhoa joined DemDx as an NED in 2015. She has over 25 years in private equity and investment banking, across Europe and Asia, including experience with Deutsche Bank, Lehman Brothers and as co-founder of TDR Capital. Tyhoa joined Dem Dx as she was struck by the value proposition to so many types of health care users.

The Board


We are very proud to work with leading health organisations such as the NHS, with leading medical professionals and leading health teaching universities.



CE mark (developed in compliance with directive 93/42/EEC for class I devices). Made in the United Kingdom.
Dem DX Clinical Reasoning Support Ref R1 (C) 2015-2022.

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We develop secure software following ISO27001 standards, our company is certified by Cyber Essentials.
Our application has passed penetration tests using the Common Vulnerability Scoring System.