Table 3.

Comparison of regression equations between A1C and AG for subgroups

	Comparison	Difference in slope	Difference in intercept	P*
Sex	Male vs. female	0.17 ± 1.14	0.57 ± 7.94	0.91
Diabetes type	Type 1 vs. type 2	−1.46 ± 1.61	9.35 ± 11.21	0.41
Age, type 1 diabetes	1st vs. 2nd tertile	−1.03 ± 2.27	−5.61 ± 16.56	0.71
	1st vs. 3rd tertile	1.53 ± 2.37	−6.99 ± 17.59	0.18
	2nd vs. 3rd tertile	0.50 ± 2.47	−1.38 ± 18.29	0.69
Age, type 2 diabetes	1st vs. 2nd tertile	−7.40 ± 3.67	52.00 ± 24.43	0.08
	1st vs. 3rd tertile	−1.57 ± 3.36	11.59 ± 22.31	0.84
	2nd vs. 3rd tertile	5.83 ± 3.07	−40.41 ± 21.45	0.17
Ethnicity	Caucasian vs. African/African-American	3.87 ± 1.85	23.35 ± 12.48	0.07
	Caucasian vs. Hispanic	−1.80 ± 3.12	5.89 ± 20.51	0.81
	Hispanic vs. African/African-American	−2.06 ± 3.49	17.46 ± 22.94	0.43
Smoking	Never vs. current	2.62 ± 1.48	−16.76 ± 10.93	0.14

Data are means ± SE.

*χ² test with 2 d.f. comparing the intercept and slope simultaneously.