Table 1.

Summary of Characteristics of the Study Population at Entry

Placebo
(n = 500)
Palivizumab
(n = 1002)
P
Value
Gender, %
 Male56.856.91.000
 Female43.243.1
Race/ethnicity, %
 White57.458.4.412
 Black25.622.8
 Hispanic10.811.0
 Asian2.42.1
 Other3.85.8
Mean (SE) birth weight, kg 1.3 (0.02) 1.3 (0.02).737
Mean (SE) gestational age, wk29 (0.14)29 (0.10).834
 Proportion ≤32 wk, %83.483.8
 Proportion >32 wk, %16.616.2
Multiple birth, %27.431.7.095
Mean (SE) weight at entry, kg 4.9 (0.1) 4.8 (0.1).335
Mean (SE) age at entry, mo 6.0 (0.21) 5.7 (0.15).215
Previous RSV, %5.63.8.111
RSV neutralizing antibody
≥1:200, %
5.65.5.895
Mean (SE) no. people in house 3.5 (0.07) 3.5 (0.05).273
No smoker in household, %68.663.0.039
Child in day care, %6.86.7.913
Family history of:, %
 Asthma35.236.1.732
 Hay fever29.628.6.717
 Eczema16.416.51.000
  • Abbreviations: SE, standard error; RSV, respiratory syncytial virus.