ageonset_Tier1
Item
Age at PD onset (cases only), Tier1
text
agestudy_Tier1
Item
Age at entry into study, Tier1
text
Item
Case-sib status, Tier1
text
Code List
Case-sib status, Tier1
labid_Tier1
Item
Dummy identifier, Tier1
text
matchnum_Tier1
Item
Identifier for each case-sib pair, Tier1
text