PubMed Health⌕ Search

Biomedical subjects

Brady Hamilton

Publications and source records attributed to Brady Hamilton.

2 recordsLinked to original sources
PubMed2004

Delayed interval delivery and infant survival: a population-based study.

OBJECTIVE: Delaying delivery of the remaining fetus(es) in a multifetal pregnancy is feasible in some cases. However, the impact of this procedure on infant survival is unclear. STUDY DESIGN: We used the US 1995-1998 Matched Multiple Birth File. We identified 200 twin pregnancies in which the first twin was delivered between 17 and 29 weeks of gestation and the second twin was delivered 2 or more days later. We individually matched the delayed deliveries with 374 twin pregnancies in which the second twin was delivered on the same or next calendar day. Perinatal outcomes and infant survival were compared between the delayed and nondelayed twins. RESULTS: Among the 200 pregnancies with delayed delivery, the mean gestational age at first delivery was 23 weeks and the median duration of delay was 6 days (ranging from 2-107 days). One week of delay in delivery was associated with an increase in infant birth weight of 131 g on average (95% CI: 115-147 g). Moreover, 56% of the delayed second twins survived to 1 year of age, whereas only 24% of the nondelayed second twins survived to 1 year of age (P <.001). However, 11% of the second twin in delayed delivery (95% CI: 6%-16%) experienced fetal death before 24 weeks. CONCLUSION: Delayed delivery of the remaining fetus(es) before 30 weeks of gestation for 2 or more days was associated with improved infant survival.

Birth Weight↗
PubMed2003

United States Census 2000 population with bridged race categories.

OBJECTIVES: The objectives of this report are to document the methods developed at the National Center for Health Statistics (NCHS) to bridge the Census 2000 multiple-race resident population to single-race categories and to describe the resulting bridged race resident population estimates. METHOD: Data from the pooled 1997-2000 National Health Interview Surveys (NHIS) were used to develop models for bridging the Census 2000 multiple-race population to single-race categories. The bridging models included demographic and contextual covariates, some at the person-level and some at the county-level. Allocation probabilities were obtained from the regression models and applied to the Census Bureau's April 1, 2000, Modified Race Data Summary File population counts to assign multiple-race persons to single-race categories. RESULTS: Bridging has the most impact on the American Indian and Alaska Native (AIAN) and Asian or Pacific Islander (API) populations, a small impact on the Black population and a negligible impact on the White population. For the United States as a whole, the AIAN, API, Black, and White bridged population counts are 12.0, 5.0, 2.5, and 0.5 percent higher than the corresponding Census 2000 single-race counts. At the sub-national level, there is considerably more variation than observed at the national level. The bridged single-race population counts have been used to calculate birth and death rates produced by NCHS for 2000 and 2001 and to revise previously published rates for the 1990s, 2000, and 2001. The bridging methodology will be used to bridge postcensal population estimates for later years. The bridged population counts presented here and in subsequent years may be updated as additional data become available for use in the bridging process.

Censuses↗