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"""
Generate vkatg/phi-audit-trace-benchmark dataset.
Author: Venkata Krishna Azith Teja Ganti
Produces synthetic clinical records paired with masking decisions,
audit hashes, policy contracts, and pre/post risk scores.
Outputs: data/train.jsonl, data/test.jsonl
"""
import hashlib
import json
import os
import random
import time
from typing import Dict, List, Tuple # noqa
random.seed(42)
MODALITIES = ["text", "asr", "image_proxy", "waveform_proxy", "audio_proxy"]
POLICIES = ["raw", "weak", "pseudo", "redact", "synthetic"]
NAMES = ["John Smith", "Maria Garcia", "David Lee", "Sarah Johnson", "Robert Chen",
"Emily Brown", "James Wilson", "Linda Martinez", "Michael Taylor", "Susan Anderson",
"Carlos Rivera", "Patricia Moore", "Kevin Zhang", "Angela White", "Thomas Harris"]
LOCATIONS = ["Boston Medical Center", "Mayo Clinic", "Johns Hopkins",
"Cleveland Clinic", "Stanford Medical", "UCSF Health"]
STREETS = ["Oak", "Main", "Elm", "Cedar", "Pine", "Maple", "Birch"]
CITIES = ["Springfield", "Riverside", "Fairview", "Lakewood", "Maplewood"]
TEMPLATES = [
"Patient {NAME} (DOB {DOB}, MRN {MRN}) presented with chest pain at {LOCATION}.",
"Spoke with {NAME} at {PHONE}. Address on file: {ADDRESS}.",
"Lab results for {NAME}, {AGE} year old from {LOCATION}, reviewed on {DATE}.",
"{NAME} (MRN {MRN}) discharged on {DATE}. Follow up at {LOCATION}.",
"Emergency contact for {NAME}: {PHONE}. DOB: {DOB}.",
"Patient identified as {NAME}, SSN {SSN}, residing at {ADDRESS}.",
"Referral sent for {NAME} (DOB {DOB}) to specialist in {LOCATION}.",
"Confirmed identity of {NAME} via MRN {MRN} and DOB {DOB}.",
"{NAME} called from {PHONE} reporting symptoms. Age: {AGE}.",
"Record updated for {NAME} at {ADDRESS} on {DATE}.",
]
SYNTH_MAP = {
"NAME": "Alex Morgan", "DOB": "1980-01-01", "MRN": "MRN-000000",
"ADDRESS": "100 Generic Ave, Anytown", "PHONE": "(000) 000-0000",
"SSN": "000-00-0000", "DATE": "2000-01-01", "AGE": "45",
"LOCATION": "General Hospital", "EMAIL": "patient@example.com",
}
def _rand_phi(rng: random.Random) -> Dict[str, str]:
y = rng.randint(1935, 1985)
m = rng.randint(1, 12)
d = rng.randint(1, 28)
return {
"NAME": rng.choice(NAMES),
"DOB": "%04d-%02d-%02d" % (y, m, d),
"MRN": "MRN-%06d" % rng.randint(100000, 999999),
"ADDRESS": "%d %s St, %s" % (rng.randint(100, 999), rng.choice(STREETS), rng.choice(CITIES)),
"PHONE": "(%03d) %03d-%04d" % (rng.randint(200, 999), rng.randint(100, 999), rng.randint(1000, 9999)),
"SSN": "%03d-%02d-%04d" % (rng.randint(100, 999), rng.randint(10, 99), rng.randint(1000, 9999)),
"DATE": "20%02d-%02d-%02d" % (rng.randint(0, 23), rng.randint(1, 12), rng.randint(1, 28)),
"AGE": str(rng.randint(18, 95)),
"LOCATION": rng.choice(LOCATIONS),
"EMAIL": "patient%d@example.com" % rng.randint(1000, 9999),
}
def _render(template: str, phi: Dict[str, str]) -> Tuple[str, List[Dict]]:
text = template
spans = []
for phi_type, val in phi.items():
ph = "{%s}" % phi_type
if ph not in text:
continue
start = text.index(ph)
text = text.replace(ph, val, 1)
spans.append({"phi_type": phi_type, "value": val, "start": start, "end": start + len(val)})
spans.sort(key=lambda x: x["start"])
return text, spans
def _risk(spans: List[Dict], modality: str, cross_modal: bool) -> float:
types = {s["phi_type"] for s in spans}
base = min(0.15 * len(spans), 0.80)
if "NAME" in types and "DOB" in types:
base += 0.10
if cross_modal:
base += 0.12
if modality in ("image_proxy", "audio_proxy"):
base += 0.05
return round(min(base, 0.99), 4)
def _policy(risk: float, consent: str) -> str:
if consent == "minimal":
return "raw"
if risk >= 0.65:
return "redact"
if risk >= 0.45:
return "pseudo"
if risk >= 0.25:
return "weak"
return "raw"
def _mask(text: str, spans: List[Dict], policy: str) -> str:
if policy == "raw":
return text
result = text
for s in reversed(spans):
val = s["value"]
pt = s["phi_type"]
if policy == "redact":
rep = "[REDACTED]"
elif policy == "pseudo":
rep = "[%s_%s]" % (pt, hashlib.md5(val.encode()).hexdigest()[:6])
elif policy == "weak":
if pt == "DOB":
rep = val[:7] + "-XX"
elif pt == "AGE":
a = int(val)
rep = "%d-%d" % ((a // 10) * 10, (a // 10) * 10 + 9)
else:
rep = "[%s]" % pt
else:
rep = SYNTH_MAP.get(pt, "[SYNTHETIC]")
result = result[:s["start"]] + rep + result[s["end"]:]
return result
def _audit_hash(record_id: str, policy: str, risk: float, spans: List[Dict]) -> str:
payload = json.dumps({
"record_id": record_id,
"policy": policy,
"risk": risk,
"phi_types": sorted({s["phi_type"] for s in spans}),
}, sort_keys=True)
return hashlib.sha256(payload.encode()).hexdigest()
RISK_REDUCTION = {"raw": 1.0, "weak": 0.75, "pseudo": 0.50, "redact": 0.10, "synthetic": 0.35}
def generate_record(idx: int, rng: random.Random) -> Dict:
record_id = "AUDIT-%06d" % idx
modality = rng.choice(MODALITIES)
consent = rng.choice(["minimal", "standard", "research", "full"])
cross_modal = rng.random() < 0.25
template = rng.choice(TEMPLATES)
phi = _rand_phi(rng)
text, spans = _render(template, phi)
risk_before = _risk(spans, modality, cross_modal)
pol = _policy(risk_before, consent)
masked = _mask(text, spans, pol)
risk_after = round(risk_before * RISK_REDUCTION[pol], 4)
audit_hash = _audit_hash(record_id, pol, risk_before, spans)
return {
"record_id": record_id,
"modality": modality,
"consent_level": consent,
"cross_modal": cross_modal,
"original_text": text,
"masked_text": masked,
"phi_spans": spans,
"policy_contract": {
"chosen_policy": pol,
"risk_score_before": risk_before,
"risk_score_after": risk_after,
"consent_level": consent,
"modality": modality,
"policy_version": "v1",
},
"audit": {
"audit_hash": audit_hash,
"timestamp_unix": int(time.time()) - rng.randint(0, 86400 * 30),
"phi_types_detected": sorted({s["phi_type"] for s in spans}),
"span_count": len(spans),
},
}
def main():
os.makedirs("data", exist_ok=True)
rng = random.Random(42)
train = [generate_record(i, rng) for i in range(4000)]
test = [generate_record(i, rng) for i in range(4000, 5000)]
with open("data/train.jsonl", "w") as f:
for r in train:
f.write(json.dumps(r) + "\n")
with open("data/test.jsonl", "w") as f:
for r in test:
f.write(json.dumps(r) + "\n")
print("train: %d test: %d" % (len(train), len(test)))
pol_dist = {}
for r in train:
p = r["policy_contract"]["chosen_policy"]
pol_dist[p] = pol_dist.get(p, 0) + 1
print("policy dist:", pol_dist)
risks = [r["policy_contract"]["risk_score_before"] for r in train]
print("avg risk before: %.3f" % (sum(risks) / len(risks)))
print("avg risk after: %.3f" % (sum(r["policy_contract"]["risk_score_after"] for r in train) / len(train)))
if __name__ == "__main__":
main()