Table 2. Comparison of weight, length and head circumference z-scores and rates of subnormal scores (−2 s.d.) at birth, 40 weeks, 8 and 20 months corrected age between period I (1996–1999) and period II (2000–2003).

	Birth			40 weeks			20 months
	Period I	Period II	P-value	Period I	Period II	P-value	Period I	Period II	P-value
	n=117	n=105		n=117	n=105		n=117	n=105
Weight
z-scorea	−0.18±0.7	−0.20±0.7	0.829	−1.84±0.9	−1.69±0.9	0.204	−1.60±1.5	−1.22±1.3	0.041
z-score <−2 s.d.	0	0		46%	38%	0.259	40%	21%	0.002
Length
z-scorea	−1.46±1.3	−1.31±1.1	0.370	−2.87±1.4	−2.63±1.4	0.184	−0.96±1.3	−0.73±1.1	0.150
z-score <−2 s.d.	31%	29%	0.721	77%	66%	0.073	16%	9%	0.086
Head circumference
z-scorea	−0.13±0.9	−0.28±0.8	0.137	−0.99±1.2	−0.89±1.4	0.494	−0.46±1.1	−0.43±1.2	0.851
z-score <−2 s.d.	0.8%	0%	1.000	20%	24%	0.554	9%	8%	0.800

^aBirth and 40 weeks^{14, 15} and 20 months.¹⁶