> For the complete documentation index, see [llms.txt](https://docs.snomed.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.snomed.org/snomed-ct-practical-guides/snomed-ct-postcoordination-guide/expressions-in-the-ehr/storing-patient-data-using-expressions.md).
# Storing Patient Data using Expressions
Storing Patient Data using Expressions
When implementing postcoordinated SNOMED CT expressions, there are different approaches to storage that may be considered.
* [Store the full expression in the same way as you would store any coded data item](/snomed-ct-practical-guides/snomed-ct-postcoordination-guide/expressions-in-the-ehr/storing-patient-data-using-expressions/store-the-full-expression.md)
* [Reference the expression in the record storage using a local expression identifier, and hold the expressions in a separate expression repository](/snomed-ct-practical-guides/snomed-ct-postcoordination-guide/expressions-in-the-ehr/storing-patient-data-using-expressions/store-expression-identifier.md)
* [Store the expression parts individually in separate fields](/snomed-ct-practical-guides/snomed-ct-postcoordination-guide/expressions-in-the-ehr/storing-patient-data-using-expressions/store-expression-parts-individually.md)
These approaches are described in the following pages.
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