# CTCAE Grading Engine

Purpose: Rule-based engine for grading chemotherapy toxicity

Usage:

def grade_symptom(symptom: str, severity: int) -> dict:
    """Grade a symptom based on CTCAE criteria."""
    rules = load_ctcae_rules()
    if symptom not in rules:
        return {"grade": 0, "error": "Unknown symptom"}
    
    rule = rules[symptom]
    grade = min(severity, 4)  # Max grade 4 for MVP
    provisional = grade >= 2  # Grade >= 2 needs confirmation
    
    return {
        "term": symptom,
        "grade": grade,
        "criteria": rule["criteria"][grade],
        "provisional": provisional
    }

Notes:

• Grade 1: Mild, no intervention

• Grade 2: Moderate, intervention needed

• Grade 3: Severe, hospitalization

• Grade 4: Life-threatening

• Grade >= 2 flagged provisional until clinician confirms

Source: HAD Digital MVP (ctcae_engine.py)