Update README.md

README.md

@@ -14,9 +14,67 @@ configs:
     path: data_subset.csv
 ---
 
-# POU
+# OMOP POU Data Card
 
-Three separate CSV tables:
-- cohort
-- covariates
-- data
+----------------------------------
+
+## Publication
+
+Naderalvojoud, Behzad, et al.  
+"Towards global model generalizability: independent cross-site feature evaluation for patient-level risk prediction models using the OHDSI network."  
+*Journal of the American Medical Informatics Association* 31.5 (2024): 1051–1061.
+
+Please refer to the publication for full details on cohort construction and model development.
+
+---
+
+## Dataset Specification
+
+- **Source of Data**: STARR OMOP  
+- **Prediction outcome**: Prolonged opioid use  
+  - 1: Prolonged  
+  - 0: Non-prolonged  
+- **Covariate count**: 10,636  
+- **Total cohort size (original)**: 41,929 patients  
+- **Final modeling cohort**: 41,507 patients  
+- **Training set size**: 33,206  
+- **Test set size**: 8,301  
+
+---
+
+## Note on Data Availability
+
+Due to PHI restrictions, the full dataset cannot be publicly released. The files provided here are **small subset examples with synthetic patients**, intended only to demonstrate the **structure and format** of the dataset.
+
+---
+
+## File Descriptions
+
+### `cohort_subset.csv`
+
+Contains 10 example (synthetic) patients with:
+- `rowId`: patient identifier  
+- `outcome`: prolonged opioid use label  
+
+---
+
+### `data_subset.csv`
+
+Represents the model input matrix:
+- Each row corresponds to a patient  
+- Each column corresponds to a covariate (by covariateId)  
+- `rowId` links to `cohort_subset.csv`  
+
+---
+
+### `covariate_subset.csv`
+
+Covariate dictionary containing:
+- `covariateId`  
+- `covariateName`  
+
+---
+
+## Support 
+
+Please contact Dr. Behzad Naderalvojoud at behzadn@stanford.edu for any questions or clarifications regarding this dataset.