A national study of health care service utilization and substance use after the 2010 Chilean earthquake.

Objective: A national epidemiological survey in Chile assessed adaptive (health care utilization) and maladaptive (substance use) postearthquake behaviors.

Methods: Three months after the 8.8-magnitude 2010 Bio-Bio earthquake, face-to-face interviews were conducted with a representative sample of 2,108 adults. Logistic regression analyses examined predictors of health care service utilization and substance use.

Results: Few participants utilized available government- and community-based psychosocial resources (16.6%). A minority reported increased substance use (13.2%). Lower self-efficacy was correlated with increased health care utilization (odds ratio [OR]=.92, 95% confidence interval [CI]=.88-.96) and use of tranquilizers, illicit and psychotropic drugs, and alcohol (OR=.95, CI=.91-.99); this pattern was not limited to residents of areas with the heaviest impacts.

Conclusions: Self-efficacy beliefs elucidate variability in survivors' behaviors postdisaster and may provide an avenue to encourage salubrious responses. Postdisaster interventions should broadly target the population; those less heavily affected may need, and be as likely to use, available resources.