<qa>  What is the main theme of the WHOs review of the effectiveness of worldwide intervention strategies?The WHO has reviewed the effectiveness of worldwide intervention strategies and made recommendations to promote violence prevention throughout the world. Some of the common themes across all countries included: 1 because families play a fundamental role in influencing the propensity for violent behavior, efforts to provide parents with information and strategies for raising nonviolent children are needed; and 2 early interventions to reduce childhood exposure to violence are essential. 