```json { "classifications": [ {"column": "STUDYID", "role": "identifier", "confidence": 1.0, "reason": "Study identifier code, used to identify the study"}, {"column": "USUBJID", "role": "identifier", "confidence": 1.0, "reason": "Unique subject identifier, primary key with 306 distinct values for 306 rows"}, {"column": "SUBJID", "role": "identifier", "confidence": 1.0, "reason": "Subject ID, unique identifier with 306 distinct values"}, {"column": "RFSTDTC", "role": "dimension", "confidence": 0.9, "reason": "Reference start date, used for temporal filtering and grouping"}, {"column": "RFENDTC", "role": "dimension", "confidence": 0.9, "reason": "Reference end date, used for temporal filtering and grouping"}, {"column": "RFXSTDTC", "role": "dimension", "confidence": 0.9, "reason": "Treatment start date, used for temporal analysis"}, {"column": "RFXENDTC", "role": "dimension", "confidence": 0.9, "reason": "Treatment end date, used for temporal analysis"}, {"column": "RFICDTC", "role": "dimension", "confidence": 0.7, "reason": "Date field with only missing values, likely temporal dimension"}, {"column": "RFPENDTC", "role": "dimension", "confidence": 0.9, "reason": "Reference period end date, high cardinality temporal dimension"}, {"column": "DTHDTC", "role": "dimension", "confidence": 0.9, "reason": "Death date, low cardinality temporal dimension for filtering"}, {"column": "DTHFL", "role": "dimension", "confidence": 1.0, "reason": "Death flag, binary categorical dimension for filtering"}, {"column": "SITEID", "role": "identifier", "confidence": 0.9, "reason": "Site identifier code, foreign key with 17 distinct sites"}, {"column": "AGE", "role": "measure", "confidence": 1.0, "reason": "Numeric age value to be aggregated (avg, median)"}, {"column": "AGEU", "role": "dimension", "confidence": 1.0, "reason": "Age unit, categorical dimension with single value"}, {"column": "SEX", "role": "dimension", "confidence": 1.0, "reason": "Gender category, used for grouping and filtering"}, {"column": "RACE", "role": "dimension", "confidence": 1.0, "reason": "Race category, used for grouping and filtering"}, {"column": "ETHNIC", "role": "dimension", "confidence": 1.0, "reason": "Ethnicity category, used for grouping and filtering"}, {"column": "ARMCD", "role": "identifier", "confidence": 0.9, "reason": "Treatment arm code, categorical identifier for treatment groups"}, {"column": "ARM", "role": "dimension", "confidence": 1.0, "reason": "Treatment arm description, categorical dimension for grouping"}, {"column": "ACTARMCD", "role": "identifier", "confidence": 0.9, "reason": "Actual treatment arm code, categorical identifier"}, {"column": "ACTARM", "role": "dimension", "confidence": 1.0, "reason": "Actual treatment arm description, categorical dimension"}, {"column": "COUNTRY", "role": "dimension", "confidence": 1.0, "reason": "Country category, geographic dimension with single value"}, {"column": "DMDTC", "role": "dimension", "confidence": 0.9, "reason": "Demographics date, temporal dimension for analysis"}, {"column": "DMDY", "role": "measure", "confidence": 0.8, "reason": "Study day numeric value, likely aggregated for analysis"}, {"column": "TRT01P", "role": "dimension", "confidence": 1.0, "reason": "Planned treatment, categorical dimension for grouping"}, {"column": "TRT01A", "role": "dimension", "confidence": 1.0, "reason": "Actual treatment, categorical dimension for grouping"}, {"column": "TRTSDTM", "role": "dimension", "confidence": 0.9, "reason": "Treatment start datetime, temporal dimension"}, {"column": "TRTSTMF", "role": "dimension", "confidence": 1.0, "reason": "Treatment start time flag, categorical dimension"}, {"column": "TRTEDTM", "role": "dimension", "confidence": 0.9, "reason": "Treatment end datetime, temporal dimension"}, {"column": "TRTETMF", "role": "dimension", "confidence": 1.0, "reason": "Treatment end time flag, categorical dimension"}, {"column": "TRTSDT", "role": "dimension", "confidence": 0.9, "reason": "Treatment start date, temporal dimension"}, {"column": "TRTEDT", "role": "dimension", "confidence": 0.9, "reason": "Treatment end date, temporal dimension"}, {"column": "TRTDURD", "role": "measure", "confidence": 1.0, "reason": "Treatment duration numeric value, aggregated for analysis"}, {"column": "SCRFDT", "role": "dimension", "confidence": 0.9, "reason": "Screen failure date, temporal dimension"}, {"column": "EOSDT", "role": "dimension", "confidence": 0.9, "reason": "End of study date, temporal dimension"}, {"column": "EOSSTT", "role": "dimension", "confidence": 1.0, "reason": "End of study status, categorical dimension for grouping"}, {"column": "FRVDT", "role": "dimension", "confidence": 0.9, "reason": "Follow-up visit date, temporal dimension"}, {"column": "RANDDT", "role": "dimension", "confidence": 0.9, "reason": "Randomization date, temporal dimension"}, {"column": "DTHDT", "role": "dimension", "confidence": 0.9, "reason": "Death date, temporal dimension"}, {"column": "DTHDTF", "role": "dimension", "confidence": 0.8, "reason": "Death date flag, categorical dimension with single value"}, {"column": "DTHADY", "role": "measure", "confidence": 0.9, "reason": "Death study day, numeric value for aggregation"}, {"column": "LDDTHELD", "role": "measure", "confidence": 0.8, "reason": "Days elapsed to death, numeric value for aggregation"}, {"column": "DTHCAUS", "role": "dimension", "confidence": 1.0, "reason": "Death cause category, used for grouping"}, {"column": "DTHDOM", "role": "dimension", "confidence": 1.0, "reason": "Death domain category, used for grouping"}, {"column": "DTHCGR1", "role": "dimension", "confidence": 1.0, "reason": "Death category, used for grouping"}, {"column": "LSTALVDT", "role": "dimension", "confidence": 0.9, "reason": "Last alive date, temporal dimension"}, {"column": "SAFFL", "role": "dimension", "confidence": 1.0, "reason": "Safety flag, binary categorical dimension for filtering"}, {"column": "RACEGR1", "role": "dimension", "confidence": 1.0, "reason": "Race group category, used for grouping"}, {"column": "AGEGR1", "role": "dimension", "confidence": 1.0, "reason": "Age group category, used for grouping"}, {"column": "REGION1", "role": "dimension", "confidence": 1.0, "reason": "Region category, geographic dimension"}, {"column": "LDDTHGR1", "role": "dimension", "confidence": 1.0, "reason": "Death elapsed group category, used for grouping"}, {"column": "DTH30FL", "role": "dimension", "confidence": 1.0, "reason": "Death within 30 days flag, binary categorical dimension"}, {"column": "DTHA30FL", "role": "dimension", "confidence": 0.8, "reason": "Death after 30 days flag, categorical dimension with single value"}, {"column": "DTHB30FL", "role": "dimension", "confidence": 1.0, "reason": "Death before 30 days flag, binary categorical dimension"} ] } ```