Slide Presentation of the 2007 Annual Meeting of AHRQ

Advantages of Observational Studies

• RCT's rarely powered for ADE's.
• RCT's have poor external validity.
  • May not generalize to the patient population for whom the intervention may be applied.
    • Women, children, minorities, very elderly are under-represented.
    • Multiple drug choices and alternatives.
    • Co-morbid conditions.
    • RCT setting, health care providers is "artificial".
• Longer term follow-up is usually achievable.
• Facilitates risk management and risk minimization.
• Enables better translation.
  • Interventions that are efficacious under a highly specific set of circumstances often fail to replicate across a wide variety of settings, conditions, patients.