diff --git a/xsd/tdwg_dwcterms.xsd b/xsd/tdwg_dwcterms.xsd
index ec56b62..809319d 100644
--- a/xsd/tdwg_dwcterms.xsd
+++ b/xsd/tdwg_dwcterms.xsd
@@ -184,8 +184,8 @@
     <xs:element name="fieldNumber" type="xs:string" substitutionGroup="dwc:anyEventTerm"/>
     <xs:element name="samplingProtocol" type="xs:string" substitutionGroup="dwc:anyEventTerm"/>
     <xs:element name="samplingEffort" type="xs:string" substitutionGroup="dwc:anyEventTerm"/>
-    <xs:element name="sampleValueSize" type="xs:string" substitutionGroup="dwc:anyEventTerm"/>
-    <xs:element name="sampleValueUnit" type="xs:string" substitutionGroup="dwc:anyEventTerm"/>
+    <xs:element name="sampleSizeValue" type="xs:string" substitutionGroup="dwc:anyEventTerm"/>
+    <xs:element name="sampleSizeUnit" type="xs:string" substitutionGroup="dwc:anyEventTerm"/>
     <xs:element name="fieldNotes" type="xs:string" substitutionGroup="dwc:anyEventTerm"/>
     <xs:element name="eventRemarks" type="xs:string" substitutionGroup="dwc:anyEventTerm"/>
     <xs:group name="EventTerms">