|
Gestational age/Birth weight
|
1995-2005
|
2005
|
|---|
|
Rate (95 % CI)
|
Rate Ratio (95 % CI)
|
Rate (95 % CI)
|
Rate Ratio (95 % CI)
|
|---|
|
GA (weeks)
|
≥22
|
Canada
|
1.6 (1.5–1.6)
|
1.62 (1.57–1.68)
|
1.4 (1.2–1.5)
|
1.54 (1.36–1.73)
|
|
USA
|
2.4 (2.3–2.4)
|
2.41 (2.40–2.43)
|
2.3 (2.3–2.3)
|
2.59 (2.54–2.65)
|
|
Denmark
|
1.2 (1.1–1.3)
|
1.17 (1.09–1.25)
|
1.0 (0.8–1.3)
|
1.12 (0.86–1.43)
|
|
Finland
|
1.0 (1.0–1.1)
|
1.00
|
0.9 (0.7–1.2)
|
1.00
|
|
Norway
|
1.1 (1.1–1.2)
|
1.18 (1.09–1.26)
|
0.7 (0.5–1.0)
|
0.79 (0.56–1.08)
|
|
Sweden
|
1.1 (1.0–1.2)
|
1.14 (1.07–1.21)
|
1.1 (0.9–1.3)
|
1.19 (0.98–1.44)
|
|
≥28
|
Canada
|
1.5 (1.4–1.5)
|
1.49 (1.44–1.54)
|
1.2 (1.1–1.4)
|
1.43 (1.26–1.61)
|
|
USA
|
2.1 (2.1–2.1)
|
2.13 (2.11–2.14)
|
2.0 (1.9–2.0)
|
2.32 (2.27–2.37)
|
|
Denmark
|
1.2 (1.1–1.2)
|
1.15 (1.07–1.23)
|
0.9 (0.7–1.2)
|
1.04 (0.79–1.35)
|
|
Finland
|
1.0 (0.9–1.1)
|
1.00
|
0.9 (0.6–1.1)
|
1.00
|
|
Norway
|
1.0 (1.0–1.1)
|
1.06 (0.98–1.15)
|
0.6 (0.4–0.8)
|
0.70 (0.48–0.98)
|
|
Sweden
|
1.0 (0.9–1.1)
|
1.03 (0.96–1.09)
|
0.9 (0.7–1.1)
|
1.07 (0.86–1.31)
|
|
BW (grams)
|
≥500
|
Canada
|
1.6 (1.5–1.6)
|
1.57 (1.52–1.62)
|
1.4 (1.2–1.5)
|
1.53 (1.36–1.72)
|
|
USA
|
2.3 (2.3–2.3)
|
2.32 (2.30–2.33)
|
2.3 (2.2–2.3)
|
2.56 (2.51–2.61)
|
|
Denmark
|
1.2 (1.1–1.3)
|
1.18 (1.10–1.26)
|
1.0 (0.8–1.3)
|
1.12 (0.86–1.42)
|
|
Finland
|
1.0 (0.9–1.1)
|
1.00
|
0.9 (0.7–1.2)
|
1.00
|
|
Norway
|
1.1 (1.1–1.2)
|
1.13 (1.05–1.22)
|
0.7 (0.5–0.9)
|
0.77 (0.55–1.05)
|
|
Sweden
|
1.1 (1.0–1.2)
|
1.10 (1.04–1.16)
|
1.0 (0.9–1.3)
|
1.18 (0.97–1.43)
|
|
≥1000
|
Canada
|
1.5 (1.4–1.5)
|
1.51 (1.46–1.57)
|
1.2 (1.0–1.3)
|
1.52 (1.33–1.72)
|
|
USA
|
2.0 (2.0–2.1)
|
2.13 (2.12–2.14)
|
1.9 (1.9–2.0)
|
2.48 (2.43–2.54)
|
|
Denmark
|
1.1 (1.1–1.2)
|
1.20 (1.12–1.28)
|
0.9 (0.7–1.2)
|
1.00 (0.76–1.30)
|
|
Finland
|
1.0 (0.9–1.0)
|
1.00
|
0.8 (0.6–1.0)
|
1.00
|
|
Norway
|
1.0 (1.0–1.1)
|
1.09 (1.01–1.18)
|
0.6 (0.4–0.8)
|
0.76 (0.53–1.06)
|
|
Sweden
|
1.0 (0.9–1.1)
|
1.04 (0.98–1.11)
|
0.9 (0.7–1.1)
|
1.16 (0.93–1.42)
|
|
All live births
|
Canada
|
1.6 (1.5–1.6)
|
1.57 (1.52–1.62)
|
1.4 (1.2–1.5)
|
1.54 (1.36–1.73)
|
|
USA
|
2.4 (2.3–2.4)
|
2.34 (2.32–2.35)
|
2.3 (2.3–2.3)
|
2.60 (2.54–2.65)
|
|
Denmark
|
1.2 (1.1–1.3)
|
1.17 (1.09–1.25)
|
1.0 (0.8–1.3)
|
1.12 (0.86–1.43)
|
|
Finland
|
1.0 (0.9–1.1)
|
1.00
|
0.9 (0.7–1.2)
|
1.00
|
|
Norway
|
1.1 (1.1–1.2)
|
1.14 (1.06–1.22)
|
0.7 (0.5–1.0)
|
0.79 (0.56–1.08)
|
|
Sweden
|
1.1 (1.0–1.2)
|
1.10 (1.04–1.17)
|
1.1 (0.9–1.3)
|
1.19 (0.98–1.44)
|
- GA gestational age and BW birth weight. Rates are expressed per 1,000 infants at risk. Only births with gestational age <22 weeks excluded from the rate calculation for births ≥22 weeks i.e., births with unknown gestational age included in the calculations. Calculations of rates for births ≥28 weeks and birth weight ≥500 g and ≥1000 g were carried out in a similar manner. Finland was used as the reference category for calculation of rate ratios
