Methods, units and quality requirements for the analysis of haemoglobin A1c in diabetes mellitus

Table 3 Summary of the questionnaires about the use of the hemoglobin A_1c units sent to 35-51 societies of laboratory medicine (mainly clinical chemistry) and returned by 28.12.2014

Year	2009	2011	2013	2014
Queries sent	35	37	47	51
Only % unit	16	14	15	17
Parallel units, % and mmol/mol	4	9	12	11
mmol/mol unit only in use	(1)	6	11	13
No reply	15	8	9	10

¹Germany was the first country which adopted the exclusive use of mmol/mol unit for HbA1c from 1.1.2010. The questionnaires have been dispatched by e-mail, telefax and mail mainly to Europe and to a small extent outside of Europe from 2009 to 2014.