According to the Blueprints for Healthy Youth Development:

• In a U.S. Population Study:
  • Positive effects in the Triple P System counties for rates of substantiated child maltreatment, child-out-of-home placements, and hospitalizations or emergency-room visits for child maltreatment injuries, compared to control counties
     
• In an Australian Population Study:
  • Triple P System was associated with significantly greater reductions in emotional problems and psycho-social distress in both children and their parents than in the care as usual condition
  • No intervention effects were found for conduct problems, hyperactivity and peer relationship difficulties.