Table 5

Regression coefficients for potential predictors of full scale IQ standard deviation scores (IQ-SDS) at 14 and 18 years

		Full scale IQ-SDS at 14 years (n = 42)				Full scale IQ-SDS at 18 years (n = 29)
		Coefficient (95% CI)	p Value			Coefficient (95% CI)	p Value
Full scale IQ-SDS at 8 years	0.86 ( 0.69 to 1.03)	<0.001		0.64 ( 0.45 to 0.84)	<0.001
PRA (per 10% of normal)	0.15 ( 0.00 to 0.29)	0.048		0.15 (−0.01 to 0.32)	0.06
Control before 8 years (per scale step5-150)	−0.09 (−0.35 to 0.18)	0.52		0.10 (−0.19 to 0.38)	0.50
Control after 8 years5-151	0.00 (−0.07 to 0.08)	0.94		−0.05 (−0.15 to 0.05)	0.29

↵5-150 Proportion of phenylalanine results between 125 and 500 μmol/litre scored as: 1, 75–100%; 2, 50–74%; 3, 25–49%; 4, 0–24%.
↵5-151 For each 100 μmol/litre increase in phenylalanine.
CI, confidence interval.