Is having more preapproval data the best way to assure drug safety?

An intensified focus on drug safety often leads to demands for more data collection prior to drug approval. Other approaches can be used, such as enhanced postmarketing surveillance. Many drug benefits and adverse effects are unlikely to become apparent before wide distribution among diverse patients. The best balance of pre- and postapproval data collection may vary by drug. The consequences of alternative strategies are complex and not always immediately apparent, so formal modeling offers the best approach to determine which strategy is optimal in each case.