LIMITATIONS
As with any retrospective database analysis, it was not possible to have
input into variables included in the tool nor to ensure accuracy of data
recording. Among variables not reported in the database were
socioeconomic status (such as income category, educational level, and
insurance status) and a measure of co-morbidities. All of these
variables could have conceivably affected D2B times of patients in the
database. Although over 1000 patients were included in the database,
only 818 had D2B times; further, the number of patients in the six
hospitals differed greatly (varying from 122 to 322). Given the large
number of variables, it is possible that the study was under-powered to
detect important differences among the hospitals.