1. Births: final data for 2014.;Hamilton;Natl Vital Stat Rep,2015
2. Reduced disparities in birth rates among teens aged 15–19 years—United States, 2006–2007 and 2013–2014.;Romero;MMWR Morb Mortal Wkly Rep,2016
3. Measuring gestational age in vital statistics data: transitioning to the obstetric estimate.;Martin;Natl Vital Stat Rep,2015
4. Components of a difference between two rates.;Kitagawa;J Am Stat Assoc,1955
5. Institute of Medicine (US) Committee on Understanding Premature Birth and Assuring Healthy Outcomes. Preterm birth: causes, consequences, and prevention. Washington, DC: National Academies Press, 2007.