Page History
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Patient_num | Encounter_num | Instance_num | Concept_cd | Start_date | Modifier_cd | ValType_Cd | Tval_char | Nval_num |
123 | 107 | 1 | cpt:59622 | 20060304 | @ | <null> | <null> | <null> |
123 | 107 | 1 | cpt:59622 | 20060304 | cptmod:62 | <null> | <null> | <null> |
123 | 107 | 1 | cpt:59622 | 20060304 | cptmod:AA | <null> | <null> | <null> |
123 | 107 | 1 | cpt:59622 | 20060304 | cptmod:TH | <null> | <null> | <null> |
123 | 567 | 1 | med:aspirin | 20100404 | @ | <null> | <null> | <null> |
123 | 567 | 1 | med:aspirin | 20100404 | MED:DOSE | N | E | 325 |
123 | 567 | 1 | med:aspirin | 20100404 | MED:ROUTE | T | QD | <null> |
123 | 567 | 1 | med:aspirin | 20100404 | MED:FREQ | T | PO | <null> |
123 | 567 | 2 | med:aspirin | 20100404 | @ | <null> | <null> | <null> |
123 | 567 | 2 | med:aspirin | 20100404 | MED:DOSE | N | E | 83 |
123 | 567 | 2 | med:aspirin | 20100404 | MED:ROUTE | T | BID | <null> |
123 | 567 | 2 | med:aspirin | 20100404 | MED:FREQ | T | PO | <null> |
P_num|E_num|Instance_num|C_CD|S_d|Modifier_CD|ValType_CD|TVal|NVal------------------------------------------------------------------123|107|1|cpt:59622|20060304|@|<null>|<null>|<null>123|107|1|cpt:59622|20060304|cptmod:62|<null>|<null>|<null>123|107|1|cpt:59622|20060304|cptmod:AA|<null>|<null>|<null>123|107|1|cpt:59622|20060304|cptmod:TH|<null>|<null>|<null>123|567|1|med:aspirin|20100404|@|<null>|<null>|<null>123|567|1|med:aspirin|20100404|MED:DOSE|N|E|325123|567|1|med:aspirin|20100404|MED:FREQ|T|QD|<null>123|567|1|med:aspirin|20100404|MED:ROUTE|T|PO|<null>123|567|2|med:aspirin|20100404|@|<null>|<null>|<null>123|567|2|med:aspirin|20100404|MED:DOSE|N|E|83123|567|2|med:aspirin|20100404|MED:FREQ|T|BID|<null>123|567|2|med:aspirin|20100404|MED:ROUTE|T|PO|<null> Looking at the medications in the example above, there are two entries for the concept med:aspirin. The only way to distinguish whether the 325 mg dose is QD or BID is to look in the instance_num column. Since the 325 mg dose has instance_num = 1, it is associated with the frequency for instance_num = 1, which is QD.
By default, the value information and data in all the non-key columns will be assumed to pertain to the modified concept, so there should usually be included a row for the base concept with an "@" in the modifier column. This will allow value information to be applied to the base concept code. Note that the modifier code is also a way that value information could be attached to the provider code.
The only change to a standard i2b2 database to enable it to work with modifiers is to add an instance number to the instance_num column. Most databases will begin with only one row per observation, and in those cases all rows can be initialized with an instance_num of "1".
The Modifier_Dimension Table and Ontology Table
The modifier_cd is a data element that describes attributes of a fact and it is a dimension column in the fact table. Information about the modifier is contained in a new dimension table in the i2b2 star schema, the modifier_dimension table.
MODIFIER_DIMENSION TABLE
Clustered primary key = modifier_path
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