Table 5. New Ballard scores and correlation to ultrasound-determined gestational age and preterm birth.
| Mean score (SD) |
Mean score of full-term (SD) |
Mean score of preterm (SD) |
Correlation with gestational age (ρ) |
|
|---|---|---|---|---|
| Skin | 2.84 (0.65) | 2.87 (0.64) | 2.68 (0.72) | 0.23*** |
| Lanugo | 1.97 (0.80) | 2.00 (0.81) | 1.82 (0.78) | 0.10 |
| Plantar Surface | 3.63 (0.54) | 3.65 (0.54) | 3.50 (0.51) | 0.13* |
| Breasts | 3.04 (0.80) | 3.13 (0.78) | 2.55 (0.74) ŦŦŦ | 0.27*** |
| Eye/Ear | 3.06 (0.50) | 3.06 (0.52) | 3.05 (0.38) | 0.15* |
| Genitals | 2.89 (0.67) | 2.94 (0.66) | 2.59 (0.67) | 0.29*** |
| Physical Maturity Subscore | 17.44 (2.06) | 17.65 (2.05) | 16.18 (1.68)^^^ | 0.35*** |
| Posture | 3.49 (0.55) | 3.54 (0.54) | 3.23 (0.53) ŦŦŦ | 0.15* |
| Square Window | 3.67 (0.51) | 3.72 (0.48) | 3.32 (0.57) ŦŦŦ | 0.28*** |
| Arm Recoil | 3.46 (0.62) | 3.51 (0.57) | 3.14 (0.77) ŦŦŦ | 0.29*** |
| Popliteal Angle | 3.41 (0.64) | 3.46 (0.66) | 3.09 (0.43) ŦŦŦ | 0.04 |
| Scarf sign | 2.92 (0.57) | 2.93 (0.58) | 2.86 (0.56) | 0.20** |
| Heel to Ear | 3.08 (0.65) | 3.14 (0.58) | 2.68 (0.89) ŦŦŦ | 0.23*** |
| Neuromuscular Maturity Subscore | 20.02 (2.00) | 20.31 (1.89) | 18.32 (1.86)^^^ | 0.33*** |
* = p<0.1,
** = p<0.05, and
*** = p<0.01 for Spearman correlation between Ballard score and ultrasound-determined gestational age at birth.
Ŧ = p<0.1,
ŦŦ = p< 0.05, and
ŦŦŦ = p < 0.01 for association between Ballard score and preterm birth by Fisher’s Exact test.
^ = p<0.1,
^^ = p< 0.05, and
^^^ = p< 0.01 for difference within subscore between full-term and preterm infants by the Wilcoxon Rank Sum test.