1. Annual summary of vital statistics-1991;Wegman;Pediatrics,1992
2. Annual summary of vital statistics-1992;Wegman;Pediatrics,1993
3. Survival of the smallest: time trends and determinants of mortality in a very preterm population during the 1980s;Heinonen;Lancet,1988
4. Decreasing mortality associated with the introduction of surfactant therapy: an observational study of neonates weighing 601 to 1300 grams at birth;Horbar;Pediatrics,1993
5. Infant mortality statistics do not adequately reflect the impact of short gestation;Carver;Pediatrics,1993