that countermeasures involving the third approach are the most effective because individual behavior is minimally affected. Indeed, groups at highest risk of injury are often the least likely to alter their behavior in response to education or legislative mandate.

Another conclusion that can be drawn from the literature is that comparatively little is known about the risk factors associated with falls; possible countermeasures are rarely researched (National Research Council, 1985). Falls rank highest among all nonfatal injuries in both incidence and cost, and constitute a leading cause of disabling conditions in the United States; nevertheless, there is limited information about the risk factors associated with falls (National Research Council, 1985).

Finally, the abuse of alcohol and drugs is known to be a major contributor to injuries of all etiology. As will be discussed in later sections, alcohol and drug use can also play an important role in recovery from major trauma in the acute and rehabilitation phases.

Although primary prevention efforts should be given highest priority, there is also a need to ensure that people who survive potentially disabling injury receive adequate acute care and rehabilitation. Meeting this need is particularly important because of the growing number of survivors who sustain severe injuries that result in significant physical and cognitive impairment, and for whom the prevention of secondary conditions is important.