Proteinuria, ^99mTc-DTPA Scintigraphy, Creatinine-, Cystatin- and Combined-Based Equations in the Assessment of Chronic Kidney Disease

Table 1

General data of certain variables at different stages of CKD.

Confidence interval for the mean at 95%
	Group	Media	Lower limit	Upper limit	Standard deviation	Interquartile amplitude
BMI	Control	23.95	22.690	25.217	3.68	2.63
	1	25.74	23.982	27.503	4.36	7.56
	2	25.95	24.764	27.133	4.26	5.47
	3	26.95	26.007	27.888	4.49	6.45
	4	29.29	27.170	31.418	6.37	6.51
	5	26.38	25.160	27.593	4.71	6.12
AGE	Control	48.63	44.25	53.006	12.74	16.00
	1	42.89	37.48	48.294	13.39	17.00
	2	45.23	41.41	49.051	13.72	18.75
	3	54.44	51.28	57.610	15.12	24.00
	4	63.22	58.47	67.963	14.24	14.50
	5	61.33	56.90	65.771	17.18	16.75
PROTEINURIA	Control	.049	.012	.087	.11	.00
	1	.37	.135	.598	.57	.41
	2	.31	.183	.426	.43	.40
	3	1.39	.708	2.075	3.26	1.14
	4	1.87	.808	1.560	.99	.71
	5	2.48	1.516	3.440	3.724	2.83
^99mTc-DTPA	Control	81.53	73.308	89.753	13.94	29.57
	1	95.26	88.605	101.944	15.80	15.77
	2	70.05	66.903	73.194	11.30	14.33
	3	45.59	43.624	47.556	9.39	14.27
	4	22.60	20.653	24.547	5.75	6.91
	5	11.18	8.989	13.364	8.40	9.79
Cystatin C	Control	.748	.717	.780	.092	.120
	1	.824	.724	.925	.249	.172
	2	.935	.846	1.024	.320	.364
	3	1.32	1.199	1.437	.569	.645
	4	1.98	1.532	2.035	.755	.850
	5	4.03	3.666	4.397	1.414	2.268

Abbreviations: CKD: chronic kidney disease; BMI: body mass index.