Although clinical signs for the diagnosis of basilar skull fracture (BSF) are 
ambiguous, they are widely used to make decisions on initial interventions 
involving trauma patients. We aimed to assess the performance of early and late 
(within 48 hr posttrauma) signs for BSF diagnosis and to verify the correlation 
between the presence of these signs and head injury severity. We conducted a 
prospectively designed follow-up study at a referral hospital for trauma care in 
Sao Paulo, Brazil, and performed structured observations for 48 hr post-blunt 
head injury in patients aged 12 years or older. The following signs of BSF were 
considered: raccoon eyes, Battle's sign, otorrhea, and rhinorrhea. Among the 136 
enrolled patients (85.3% male; mean age 40 ± 21.4 years), 28 patients (20.6%) 
had BSF. The clinical signs for the early or late detection of BSF had low 
accuracy (55.9% vs. 43.4%), specificity (52.8% vs. 30.5%), and positive 
predictive value (25.7% vs. 27.1%). However, the presence of these signs was 
correlated to head injury severity, indicated by the Glasgow Coma Scale (p = 
.041) and Maximum Abbreviated Injury Scale-Head region (p = .002). In view of 
the low accuracy of these signs, resulting low clinical value of their presence, 
and their high sensitivity in the late stage, the study results contraindicate 
the value of BSF signs for making decisions about using the nasal route for the 
introduction of catheters and tubes in initial trauma care.