CVORRES: Result of the measurement or finding as originally received or collected.
CVORRESU: Original units in which the data were collected. Unit for CVORRES.
CVSTRESC: Result value for all findings from CVORRES in a standard format or in standard units. If results are numeric, they should also be stored in numeric format in CVSTRESN.
CVSTRESN: Used for continuous or numeric results or findings in standard format; copied in numeric format from CVSTRESC.
CVSTRESU: Standardized units used for CVSTRESC and CVSTRESN.
CVLOBXFL: Last Observation Before Exposure Flag. Operationally-derived indicator used to identify the last non-missing value prior to RFXSTDTC. The value should be "Y" or null.