19 – iCGM vs eCGM vs Standardisation by the IFCC: CGM Regulation with Dr. Guido Freckmann

19 – iCGM vs eCGM vs Standardisation by the IFCC: CGM Regulation with Dr. Guido Freckmann

Full show notes and FAQ, and consider buying me a Coffee to keep pumping

Continuous glucose monitoring (CGM) has transformed diabetes care — but how do we know which systems are accurate, safe, and truly comparable? 

In this episode, John Pemberton is joined by Dr. Guido Freckmann (Institute of Diabetes Technology, Ulm; former chair of the IFCC CGM Working Group). Together they unpack: 

• Why CE marking in Europe is not a quality standard
• How the FDA’s iCGM framework (2018) was groundbreaking, but has limitations in study design
• Why the proposed eCGM model for Europe risks monopolising the market without fixing accuracy problems
• The IFCC’s roadmap towards a full ISO standard for CGM – robust, reproducible, and aligned with clinical reality

Full Show notes and FAQ, and consider buying me a Coffee to keep pumping

Key Themes & Watch-Outs

🔹 CE Mark ≠ Quality Standard

• CE marking is a regulatory pathway, not a guarantee of performance.
• Manufacturers can submit selective data, and the results are not public.

🔹 ICGM (2018): A Step Forward, But Outdated

• FDA iCGM rules set minimum standards, but study design criteria were vague.
• Devices can appear accurate by avoiding stressful glucose swings.

🔹 Why Standardisation Matters

• Standardisation would define not just performance metrics but also how studies are run.
• It would align CGM systems to the same comparator (capillary or venous) and reduce therapy discrepancies.

🔹 Capillary vs Venous Debate

• Capillary glucose reflects what people actually test and what their bodies are exposed to.
• Venous alignment risks giving a “false reassurance” of being in range.
• An agreement is needed: whichever is chosen must be standardised, with bias correction.

🔹 Clinical Impact

• Different CGMs can give the same time-in-range but very different HbA1c and complication risk.
• That undermines trust, confuses therapy adjustments, and makes clinical trial endpoints unreliable.

🔹 Looking Ahead

• CGM standardisation is in motion, but likely won’t be implemented before 2030.
• Until then, clinicians and people with diabetes need to scrutinise study design and remain critical of performance claims.

 
Quotes from the Episode

“CE marking is not a quality standard. You have to dig into study design — and that’s not practical for the average person with diabetes or most clinicians.” – John Pemberton

“CGM systems often perform worse at high rates of change than at stable glucose levels. That’s why stress-testing is vital.” – Dr. Guido Freckmann

“Different CGM systems can give the same time-in-range but very different HbA1c and complication risks. That’s unacceptable.” – John Pemberton

“Manufacturers can design studies to get good results by avoiding rapid glucose swings. Without rules, accuracy is only on paper.” – Dr. Guido Freckmann

Full Show notes and FAQ, and consider buying me a Coffee to keep pumping

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