TABLE 1

Prevalence of CP in Live Births and Infant Survivors by Birth Weight: A Comparison Between 1975–1977, 1981–1985, and 1986–1991

Birth Weight (Grams)ParameterBirth CohortCochran-Armitage Trend Test P Value
1975–1977*1981–19851986–1991
<1500Number of children with CP2784144
CP prevalence rate per 1000 infant survivors (95% CI)§65.2 (43.4, 93.5)58.6 (47.0, 72.0)59.5 (50.3, 69.6).377
CP prevalence rate per 1000 live births (95% CI)§28.5 (18.9, 41.1)36.5 (29.2, 45.0)39.7 (33.6, 46.6).054
1500–2499Number of children with CP307087
CP prevalence rate per 1000 infant survivors (95% CI)§6.9 (4.6, 9.8)7.6 (5.9, 9.6)6.2 (5.0, 7.7).224
CP prevalence rate per 1000 live births (95% CI)§6.4 (4.3, 9.1)7.4 (5.8, 9.4)6.1 (4.9, 7.5).297
>2500Number of children with CP53108212
CP prevalence rate per 1000 infant survivors (95% CI)§0.9 (0.6, 1.2)0.8 (0.7, 1.0)1.1 (0.9, 1.2).047
CP prevalence rate per 1000 live births (95% CI)§0.9 (0.6, 1.2)0.8 (0.7, 1.0)1.1 (0.9, 1.2).045
TotalNumber of children with CP110262443
CP prevalence rate per 1000 infant survivors (95% CI)§1.7 (1.4, 2.0)1.9 (1.6, 2.1)2.0 (1.9, 2.2).028
CP prevalence rate per 1000 live births (95% CI)§1.7 (1.4, 2.0)1.8 (1.6, 2.1)2.0 (1.9, 2.2).024
  • CI indicates confidence interval.

  • * CP cases identified at 10 years of age.

  • CP cases identified at 3 to 10 years of age.

  • P value presented is an asymptotic P value for a 1-sided test.

  • § Prevalence rate estimates include only children with recorded birth weight, race.

  • Number of 1-year survivors estimated by regression.