With the authorization of the
local institutional review board
(R-2012-6790-89), the study was
conducted in Hospital General of
Zona 2 A Troncoso, from the Instituto
Mexicano del Seguro Social (IMSS), and
comprised the following phases:
a) Identification of possible predictive
outcome measures: From January
2005 to December 2010, a cohort
was prospectively defined incluOriginal article
214 / Arch Argent Pediatr 2015;113(3):213-220 / Original article
ding newborn infants of any gestational age,
both genders, multiple gestations and visible
external malformations. They had to be delivered at the Obstetrical-Surgery Unit of the
Hospital, admitted at the NICU on their first
day of life and under care until discharged
for any cause. Patients born in other units were excluded and newborn infants voluntarily
withdrawn by their parents or transferred to
other hospitals were removed. The sample size calculation was based on the previous year
statistics, with a total of 3450 births and 11%
mortality, a= 95% and d= 99% (0.001), replaced
in the odds ratio formula for finite population,9
with an estimate patient number of 204. A 10%
was added to make up for estimated losses, resulting in a final calculation of 224 patient