Table 1. Brighton criteria for GBS.

+, present; -, absent; +/−, present or absent; CSF, cerebrospinal fluid; GBS, Guillain-Barré syndrome; NCS, nerve conduction study

Diagnostic criteria	Level of diagnostic certainty
	Level 1	Level 2	Level 3	Level 4
Absence of alternative diagnosis for weakness	+	+	+	+
Diminished or absent deep tendon reflex in weak limbs	+	+	+	+/−
Monophasic course and time between onset and nadir, 12 hours to 28 days	+	+	+	+/−
Bilateral and flaccid weakness of limbs	+	+	+	+/−
CSF cell count < 50 cells/microL	+	+	-	+/−
CSF protein concentration > normal value	+	+/−	-	+/−
NCS findings consistent with one of the subtypes of GBS	+	+/−	-	+/−