Update README.md

README.md

@@ -360,3 +360,84 @@ configs:
   - split: weight_full
     path: weight_data/weight_full-*
 ---
+
+# Cohort Data
+
+Processed ED patient cohort derived from MIMIC-IV. One row per ED visit (`ed_stay_id`). Built from cohort_base (BigQuery) with the following post-processing steps: 
+
+- AGAINST ADVICE discharge_location records removed — patient-driven departures are out of scope. 
+- Consecutive ED visits sharing a hadm_id collapsed into single rows; second ed_stay_id stored in `ed_stay_id_2`. 
+- `stay_window_start`/`stay_window_end` columns added covering ED arrival to final discharge. 
+- `ed_boarding_time_min` added: minutes in ED after admission decision (null for ED-only patients).
+
+Intended as the primary cohort table for feature engineering and RL state construction.  
+
+# Dispensed Meds
+
+Dispensed medication records for all cohort patients across two phases and two populations. 
+
+ED phase (`in_er`=True): Pyxis dispenses for all patients (admitted and ED-only) while physically in the ED, derived from `ed.pyxis`.  
+Ward phase (`in_er`=False): eMAR administration records for admitted patients from ED departure up to ICU transfer, derived from `hosp.emar`. 
+
+`event_txt` filtered to administration and rate-change events only. 
+
+Medication names mapped to a 22-class drug vocabulary via regex. Each record includes `minutes_into_stay` (time since ED arrival) and time_step bucket (floor(minutes / time_block)).
+
+# ECG Data
+
+ECG acuity labels derived from `mimiciv_ecg.machine_measurements` for cohort patients. Each of the 18 report columns is classified independently 
+via regex with priority order: abnormal (2) > neutral (1) > normal (0) > empty (-1). 
+
+Row-level max across all 18 columns gives `ecg_acuity`: 0=normal, 1=neutral/unknown, 2=abnormal. 
+
+Patients with all 18 columns empty are assigned 1 (missing ECG ≠ normal ECG). 
+
+Multiple ECGs per ED stay resolved to one row: highest acuity kept, ties broken by earliest ecg_time. 
+
+Window covers ED arrival through hospital ward stay (capped at ICU transfer if applicable), with ±1 hour buffer for ECG machine clock drift.
+
+# Labs Data
+
+Laboratory results from `hosp.labevents` for cohort patients during their stay window. 
+
+Grouped by category x fluid (19 unique combinations) rather than individual test label to reduce action space. 
+
+Each result includes the abnormal flag for worst-case aggregation. Intended as the primary lab state feature source.  
+
+# Medrecon Data
+
+Medication reconciliation records from `ed.medrecon` — medications the patient was taking prior to ED arrival. 
+One row per medication per ED visit. Represents pre-arrival medication state, not actions taken during the visit.  
+
+# Microbiology Data
+
+
+Microbiology culture events from `hosp.microbiologyevents` for cohort patients during their stay window. 
+Includes culture order time, specimen type, organism name, and antibiotic sensitivity results. 
+
+`culture_ordered` is the real-time state signal; culture_positive is a retrospective label only (~2% of results available before ED discharge).
+
+# OMR Data
+
+Height and weight measurement records from `hosp.omr` for cohort patients — separated to take single measurements of height as an average of all available height measurements for a patient and retaining all separate weight measurements. 
+Duplicates were dropped. Used to supplement ED and inpatient state features with recent baseline measurements.  
+
+# Radiology Data
+
+Radiology report text from `mimiciv_note.radiology` for cohort patients. Covers all imaging modalities (CXR, CT, MRI, ultrasound, etc.). 
+Primary reports only (note_type=RR). Window covers ED arrival through hospital ward stay (capped at ICU transfer if applicable).  
+`hadm_id` is NULL for ED-only patients and populated for admitted patients. `exam_name` and `cpt_code` included from radiology_detail to identify 
+imaging modality.  
+
+# Triage_Vitals
+
+Combined triage and vital signs time series — one row per (`ed_stay_id`, `charttime`) timestep. 
+Triage records (ed.triage) provide the baseline reading at `ed_intime`; subsequent vitals (`ed.vitalsign`) provide follow-up readings. 
+`stay_id` remapping applied so that vitals from a patient's second consecutive ED visit are attributed to the canonical (first) stay_id. 
+Rows recorded before `ed_intime` are dropped; records from vitals with `charttime` == `ed_intime` are dropped as duplicates of the triage records. 
+
+**Preprocessing**: `pain` column normalized and coerced to numeric, physiologically implausible vital values nulled. Missing indicators created before forward-fill. 
+Vitals forward-filled within stay, then mean-imputed for any remaining NaN. 
+
+**Feature engineering**: `time_since_last_min`, per-column deltas and rates of change (units/min), 1-hour rolling averages, mean arterial pressure (dbp + (sbp - dbp) / 3). 
+Triage rows get 0 for all delta/rate columns. Final vital columns renamed to current_{col}.