. Author manuscript; available in PMC: 2014 Sep 18.

Published in final edited form as: Eur J Epidemiol. 2010 Sep 30;25(12):855–865. doi: 10.1007/s10654-010-9512-y

Table 1.

Empirical powers of the proposed model (2.2) and the marginal model with the exchangeable (M-E) or independent (M-I) correlation structure in detecting the significant association of FPG with each of its risk factors/covariates after adjusting for the other risk factors/covariates in the model at two different significance levels (type 1 error rates) based on the 1,000 simulated data sets generated by using two different correlation matrixes R₁ and R₂

Correlation matrix	Risk factor/covariate	Significance level α = 0.05			Significance level α = 0.01

		Model (2.2)	M-E	M-I	Model (2.2)	M-E	M-I
R₁	Age (year)	0.806	0.799	0.752	0.622	0.595	0.533
	Waist (cm)	0.611	0.598	0.556	0.392	0.373	0.318
	BMI (kg/m²)	0.461	0.446	0.409	0.254	0.250	0.212
	Log(TG) (mg/dL)	0.994	0.992	0.989	0.982	0.969	0.967
	Log(UACR)	1.000	0.999	0.999	0.999	0.999	0.999
	LDL (mg/dL)	0.282	0.272	0.237	0.113	0.115	0.098
	Log(Insulin) (µU/mL)	0.379	0.389	0.342	0.173	0.184	0.144
R₂	Age (year)	0.946	0.849	0.776	0.815	0.662	0.541
	Waist (cm)	0.770	0.612	0.529	0.535	0.365	0.297
	BMI (kg/m²)	0.581	0.443	0.388	0.344	0.253	0.182
	Log(TG) (mg/dL)	1.000	0.996	0.986	0.997	0.969	0.946
	Log(UACR)	1.000	1.000	1.000	1.000	1.000	0.999
	LDL (mg/dL)	0.392	0.311	0.242	0.165	0.139	0.101
	Log(Insulin) (µU/mL)	0.565	0.443	0.369	0.346	0.224	0.166

BMI body mass index, LDL low density lipoprotein, TG triglycerides, UACR urinary albumin and creatinine ratio, Waist waist circumference