"SUSTDATPTCDISC" . "Substance Usage Start Date"^^ . "Substance_Usage_Start_Date"^^ . "Substance Usage Start Date"^^ . "Temporal Concept"^^ . "The date on which the substance usage begins.NCI" . . . . . "C2826739"^^ . "Substance Usage Start DatePTNCI" . "C83129"^^ .