Because Medicaid and Medicare traditionally have provided only treatment, these populations are left without prevention services. Perhaps the most important reason managed care organizations do not focus on preventing substance abuse or promoting mental health is that health care purchasers and managed care organizations know little about preventive interventions. The contrast between what is known about preventing infectious diseases and what is known about mental and addictive disorders is striking. Take immunization, for example. The preventive intervention represented by a vaccine typically grants a lifetime of protection.
Protocols clearly delineate the population that needs the intervention.
And outcomes are predictable. A managed care organization that vaccinates a certain number of children at an established price per vaccine knows approximately how many lives will be saved in the future by preventing people from contracting the disease. Costs can be assessed for the intervention. The same cannot be said of substance abuse prevention. Instead of targeting populations of a single age group, interventions must begin even before birth to prevent problems like fetal alcohol syndrome and continue throughout the lifespan to prevent prescription medication abuse among older people.