Out of seven medical complications, the only two that differed
between the hospitals after adjustment were cardiac and respiratory
complications. Both were relativelycommon(16%and15%overall) and
weremorefrequent in public hospital patients.However, for patientswho
did not have cardiac co-morbidity, there was no difference in cardiac
complications between the two hospitals, whereas patients with cardiac
co-morbidity had a significantly higher risk of a cardiac complication
when treated in the public hospital. This could be due to relatively greater
severity of co-morbidity in public hospital patients; however, the type and
severity of co-morbidity was not recorded in our database. In contrast
with cardiac co-morbidity, patients who did not have respiratory
co-morbidity were nevertheless at significantly higher risk of a respiratory
complication in the public hospital, whereas for those with respiratory
co-morbidity, there was no difference between the hospitals in the
rate of respiratory complications.