Prospective validation of the scale: A
prospective cohort of newborn infants was
designed using data from January 2010 to
December 2012. Selection criteria were the
same as for the previous cohort. Follow up
started at the time newborn infants were
admitted at the NICU. Outcome measures
included in this scale were taken within the
first hour of admission Based on the first
phase of the study that included 424 patients
admitted in the NICU, with a 5% mortality
rate (a= 95% and d= 99%), the odds ratio for a
finite population was estimated resulting in a
required sample size of 90 newborn infants. A
10% was added for losses and 10 patients were
added per outcome measure (90), resulting in
a final size of 189 patients.
Statistical analysis: for the descriptive statistics
central trends (s median) and scatter (interquartile ranges) were used for quantitative
outcome measures, and frequencies and
percentages were used for qualitative outcome
measures. In the first cohort, the risk by odds
ratio (OR) was calculated and a logistic regression
analysis was performed. For the second cohort, a
Cox analysis was carried out and the hazard ratio
(HR) was calculated; survival analysis by Kaplan
Meier and validity tests (sensitivity, specificity,
predictive values, likelihood values and area
under the curve) were performed for each of the
strata proposed.