Table 4.

Estimated group differences for CPI at 7 weeks, 6 months, 24 months, and 5.5 years

Estimated difference	Group differences (with 95% CI)	P-value
Mean CPI group 3 - mean CPI group 1
7 weeks of age	3.24 (1.59; 4.89)	0.0001
6 months of age	2.94 (1.29; 4.59)	0.0005
12 months of age	2.62 (0.96; 4.28)	0.002
24 months of age	1.88 (0.21; 3.55)	0.027
5.5 years	1.64 (−0.09; 3.38)	0.063
Mean CPI group 3 - mean CPI group 2
7 weeks of age	1.21 (−0.99; 3.42)	0.28
6 months of age	1.16 (−1.04; 3.37)	0.30
12 months of age	0.96 (−1.26; 3.18)	0.39
24 months of age	−0.42 (−2.67; 1.82)	0.71
5.5 years	0.77 (−1.58; 3.12)	0.52
Mean CPI group 2 - mean CPI group 1
7 weeks of age	2.02 (0.40; 3.66)	0.015
6 months of age	1.78 (0.15; 3.41)	0.032
12 months of age	1.66 (0.01; 3.30)	0.049
24 months of age	2.30 (0.63; 3.97)	0.007
5.5 years	0.87 (−0.91; 2.65)	0.34