diff --git a/spec/shr_vital.txt b/spec/shr_vital.txt
index 220f09c4..ebda3895 100644
--- a/spec/shr_vital.txt
+++ b/spec/shr_vital.txt
@@ -13,7 +13,7 @@ Element:		VitalSign
 Based on:		Test
 Concept:		LNC#8716-3 "Vital Sign"
 Value:			0..1 Quantity
-1..*			ObservationCategory includes OBSCAT#vital-sign
+1..*			ObservationCategory includes OBSCAT#vital-signs
 0..0			TBD "Specimen"  // no specimen required