Variability in Test Interval Is Linked to Glycated Haemoglobin (HbA1c) Trajectory over Time

Table 2

Association between variability in HbA1c testing intervals and change in HbA1c, by site, sex, and age. Testing interval defined as standard deviation in testing interval for those with at least 6 tests between baseline and 5 years, corrected for the number of tests and stratified by starting HbA1c; linear regression.

Starting HbA1c (mmol/mol (%))	PAT		UHNM		Female		Male		<65 years		≥65 years
		Std		Std		Std		Std		Std		Std
5.0–5.9 (30–41)	<0.0001	0.10	<0.0001	0.12	<0.0001	0.10	<0.0001	0.09	0.0107	0.04	<0.0001	0.14
6.0–6.5 (42–47)	<0.0001	0.06	<0.0001	0.06	<0.0001	0.06	0.0002	0.05	0.0008	0.04	0.0003	0.05
6.5–7.0 (48–53)	<0.0001	0.06	<0.0001	0.05	<0.0001	0.05	0.0261	0.03	0.1410	0.02	0.0194	0.03
7.0–7.5 (54–58)	<0.0001	0.10	<0.0001	0.09	<0.0001	0.10	<0.0001	0.12	<0.0001	0.08	<0.0001	0.09
7.5–9.0 (59–75)	<0.0001	0.07	<0.0001	0.08	<0.0001	0.06	<0.0001	0.08	0.0033	0.04	<0.0001	0.06
9.1–10.0 (76–86)	<0.0001	0.11	0.0046	0.07	<0.0001	0.10	0.0001	0.09	0.0879	0.06	0.0683	0.05
>10.0 (>86)	0.3146	0.02	0.0755	0.04	0.9448	0.00	0.0178	0.04	0.5444	−0.02	0.4360	0.02

Standard beta.