Editing Glycated hemoglobin (section)

==Measurement==
Several techniques are used to measure hemoglobin A1c. Laboratories may use [[high-performance liquid chromatography]], [[immunoassay]], [[enzymatic]] assay, [[capillary electrophoresis]], or [[boronate affinity chromatography]]. [[Point of care]] (e.g., doctor's office) devices use immunoassay boronate affinity chromatography.<ref name="pmid33806493"/>

In the United States, HbA<sub>1c</sub> testing laboratories are certified by the National Glycohemoglobin Standardization Program to standardize them against the results of the 1993 [[Diabetes Control and Complications Trial]] (DCCT).<ref>[http://www.devicelink.com/ivdt/archive/08/07/009.html Developing Point of care HbA1c tests for Diabetes monitoring] {{Webarchive|url=https://web.archive.org/web/20080829202705/http://www.devicelink.com/ivdt/archive/08/07/009.html |date=2008-08-29}}, Barry Plant, Originally Published IVDT July/August 2008</ref> An additional percentage scale, Mono S has previously been in use by Sweden and KO500 is in use in Japan.<ref>[Clinical Chemistry 50:1 166–174 (2004)]</ref><ref name=SDA>[http://www.hba1c.nu/HbA1c_Equalis-en.pdf HbA1c in a new way] {{Webarchive|url=https://web.archive.org/web/20130909224716/http://hba1c.nu/HbA1c_Equalis-en.pdf |date=2013-09-09}} By the Swedish Diabetes Association. Retrieved 2023-02-01.</ref>

===Switch to IFCC units===
The American Diabetes Association, [[European Association for the Study of Diabetes]], and [[International Diabetes Federation]] have agreed that, in the future, HbA<sub>1c</sub> is to be reported in the [[International Federation of Clinical Chemistry and Laboratory Medicine]] (IFCC) units.<ref name="pmid18539643">{{cite journal |vauthors=Geistanger A, Arends S, Berding C, Hoshino T, Jeppsson JO, Little R, Siebelder C, Weykamp C |title=Statistical methods for monitoring the relationship between the IFCC reference measurement procedure for hemoglobin A1c and the designated comparison methods in the United States, Japan, and Sweden |journal=Clin. Chem. |volume=54 |issue=8 |pages=1379–85 |date=August 2008 |pmid=18539643 |doi=10.1373/clinchem.2008.103556 |doi-access=free}}</ref> IFCC reporting was introduced in Europe except for the UK in 2003;<ref name="pmid15209757">{{cite journal |vauthors=Manley S, John WG, Marshall S |title=Introduction of IFCC reference method for calibration of HbA: implications for clinical care |journal=Diabet. Med. |volume=21 |issue=7 |pages=673–6 |date=July 2004 |pmid=15209757 |doi=10.1111/j.1464-5491.2004.01311.x |s2cid=30468208}}</ref> the UK carried out dual reporting from 1 June 2009 <ref>{{cite press release |title=Standardisation of the reference method for the measurement of HbA1c to improve diabetes care |date=April 2008 |publisher=[[Association for Clinical Biochemistry and Laboratory Medicine]] (with [[Diabetes UK]]) |url=http://www.acb.org.uk/docs/hba1c.pdf |access-date=2009-07-02 |url-status=dead |archive-url=https://web.archive.org/web/20110722031224/http://www.acb.org.uk/docs/hba1c.pdf |archive-date=2011-07-22}}</ref> until 1 October 2011.

Conversion between DCCT and IFCC is by the following equation:<ref name="DiabetesUK conversion">{{cite web |title=HbA1c Standardisation For Laboratory Professionals |publisher=[[Diabetes UK]] (with [[Association for Clinical Biochemistry and Laboratory Medicine]]) |url=https://www.diabetes.org.uk/resources-s3/2017-11/53130hba1chcpleaflet.pdf |access-date=2009-07-02 |url-status=live |archive-url=https://web.archive.org/web/20110720104405/http://www.diabetes.org.uk/upload/Professionals/Key%20leaflets/53130HbA1cLableaflet.pdf |archive-date=2011-07-20}}</ref>

:<math> \mathrm{IFCC\ HBA1c}\, \Big(\frac{\text{mmol}}{\text{mol}}\Big)=[\mathrm{DCCT\ HBA1c}\,(\%) - 2.14] \times 10.929 </math>

{| class="wikitable collapsible collapsed"
!"IFCC" HbA<sub>1c</sub> || "DCCT" HbA<sub>1c</sub> || "Mono S" HbA<sub>1c</sub><ref name=SDA/>
|-
| (mmol/mol) || (%) || (%)
|-
| 10 || 3.1 || 2.0
|-
| 20 || 4.0 || 2.9
|-
| 30 || 4.9 || 3.9
|-
| 40 || 5.8 || 4.8
|-
| 45 || 6.3 || 5.3
|-
| 50 || 6.7 || 5.8
|-
| 55 || 7.2 || 6.3
|-
| 60 || 7.6 || 6.8
|-
| 65 || 8.1 || 7.2
|-
| 70 || 8.6 || 7.7
|-
| 80 || 9.5 || 8.7
|-
| 90 || 10.4 || 9.6
|-
| 100|| 11.3 || 10.6
|}