Table 5.

Comparison of the results of renal function tests between extremely low birth weight (ELBW) children and control children

Renal function tests	Control (full term) group (n = 36)	Study (ELBW) group (n = 64)	p value according to Student’s t test
First follow-up (at age 7 years)
Serum cystatin C level (mg/l)	0.59 ± 0.08	0.63 ± 0.07	0.02
Second follow-up (at age 11 years)
Serum Cystatin C level (mg/l)	0.61 ± 0.08	0.72 ± 0.15	0.01
BUN (mmol/l)	4.15 ± 0.94	4.49 ± 1.03	0.028
Creatinine (umol/l)	46.3 ± 7.6	43.2 ± 7.7	0.08

Data are presented as the mean ± SD

BUN, Blood urea nitrogen