Python
# Example audit trail implementation
import hashlib
import datetime
from dataclasses import dataclass

@dataclass
class AuditEntry:
    user_id: str
    action: str
    timestamp: datetime.datetime
    record_id: str
    old_value: str
    new_value: str
    signature: str
    
def create_audit_entry(user_id, action, record_id, old_val, new_val):
    timestamp = datetime.datetime.utcnow()
    entry_data = f"{user_id}{action}{timestamp.isoformat()}{record_id}{old_val}{new_val}"
    signature = hashlib.sha256(entry_data.encode()).hexdigest()
    
    return AuditEntry(user_id, action, timestamp, record_id, old_val, new_val, signature)

Progress:

• User Access Controls: Implement role-based authentication with unique user IDs
• Electronic Signatures: Design secure signature workflows with user verification
• Audit Trail System: Create tamper-evident logging for all data changes
• Record Integrity: Implement checksums and validation for electronic records
• System Controls: Establish backup, recovery, and system security procedures
• Validation Documentation: Create IQ/OQ/PQ protocols and validation reports
• Training Records: Document user training on system procedures and Part 11 requirements

Core Requirements Implementation

1. Electronic Records (§11.10)

   • Validate system controls ensure record integrity
   • Implement audit trails for all record creation/modification/deletion
   • Ensure records are readily retrievable throughout retention period

2. Electronic Signatures (§11.50-§11.70)

   • Link signatures to their respective records permanently
   • Include time/date stamp and meaning of signature
   • Require user verification (password, biometric, etc.)

3. Controls for Closed Systems (§11.10)

   • Validation of systems to ensure accuracy and reliability
   • Generate audit trails that are computer-generated and time-stamped
   • Use operational controls and authority checks

Example 1: Audit Trail Entry Input: User "jsmith" changes batch temperature from "25.5°C" to "26.0°C" Output:

User: jsmith
Action: MODIFY_BATCH_TEMP
Timestamp: 2024-01-15T14:30:22.123Z
Record: BATCH_001
Old Value: 25.5°C
New Value: 26.0°C
Signature: a4f2b8e9c1d3f5g7h9j2k4m6n8p0q2r4
Reason: Temperature adjustment per SOP-001

Example 2: Electronic Signature Workflow Input: Document approval request for protocol validation Output:

Document: PROTOCOL_VAL_001
Signer: Dr. Sarah Johnson (QA Manager)
Signature Type: Approval
Date/Time: 2024-01-15T16:45:33.456Z
Authentication: Password + Security Question
Meaning: "I approve this validation protocol per company SOP"
Digital Signature: [cryptographic hash]