Table 1

Spearman correlations between OGTT and HbA1c

Spearman correlation coefficients Probability >\|r\| under H0: r=0 Number of observations
	Fasting blood glucose	OGTT (mmol/L) 1 h	OGTT (mmol/L) 2 h	HbA1c (%)	Ferritin	Hb
Fasting blood glucose	1.00 000
OGTT (mmol/L)/1 h	0.36 109	1.00 000
	<0.0001
	475
OGTT (mmol/L) 2 h	0.31 745	0.61 037	1.00 000
	<0.0001	<0.0001
	480	475
HbA1c (%)	0.34 298	0.21 911	0.22 906	1.00 000
	<0.0001	<0.0001	<0.0001
	438	434	438
Ferritin	0.03 316	0.11 589	0.00 636	−0.10 974	1.00 000
	0.4757	0.0129	0.8912	0.0233
	465	460	465	427
Hb	−0.03 201	0.03 996	−0.05 220	−0.26 569	0.23 075	1.00 000
	0.4860	0.3869	0.2557	<0.0001	<0.0001
	476	471	476	436	463

Hb, haemoglobin; HbA1c, glycosylated haemoglobin; OGTT, oral glucose tolerance test.