Consider the following statements about managing fraud in user referral programs. Determine which of these statements accurately reflect best practices in identifying and preventing referral fraud:
    - Statement I: Using complex algorithms to detect referral fraud is always necessary to maintain the integrity of the program.
 
    - Statement II: Regularly monitoring referral patterns and quickly investigating anomalies can effectively prevent fraud.
 
    - Statement III: Customer support teams should have clear guidelines on addressing suspected fraud cases to ensure consistent communication.
 
    - Statement IV: It's important to revise the referral program's key metrics periodically to exclude impacts of fraudulent activities.
 
Select the statement(s) that accurately reflect effective practices in managing fraud in referral programs: