Relies on i2b2 data using the ENACT ontology.
If your data uses custom code prefixes (instead of ICD10CM: and ICD9CM:), replace the prefix in the code pattern column in DT_LOYALTY_CHARLSON table.

How to

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Use the Loyalty Cohort Tool

Create a cohort filter, defining the patients on which to compute loyalty scores. The three columns are:
- patient_num: patient_num from the i2b2 tables
- cohort_name: a name for the cohort. You can optionally compute several cohorts separately, but specifying different values for this.
- index_dt: a date which is a reference point in time at which to compute the loyalty score. It is suggested to select a common recent point in time or to choose each patient's most recent visit date, for example.
Run the USP_DT_LOYALTYCOHORT stored procedure with the following parameters.

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