A randomized controlled study of single-session behavioural treatment of earthquake-related post-traumatic stress disorder using an earthquake simulator.
BACKGROUND
Brief interventions are needed in dealing with traumatic stress problems in large survivor populations after devastating earthquakes. The present study examined the effectiveness of a single session of exposure to simulated tremors in an earthquake simulator and self-exposure instructions in reducing post-traumatic stress disorder (PTSD).


METHOD
Participants were consecutively recruited from among survivors screened during field surveys in the disaster region in Turkey. Thirty-one earthquake survivors with PTSD were assigned either to a single session of behavioural treatment (n=16) or to repeated assessments (RA; n=15). Assessments in the treatment group were at 4, 8, 12, 24 weeks and 1-2 years post-treatment. The RA cases were assessed at baseline and 4 and 8 weeks after trial entry, after which they received the same treatment and were followed up at 4, 12, 24 weeks and 1-2 years.


RESULTS
Between-group treatment effects at week 8 were significant on measures of fear, PTSD and self- and assessor-rated global improvement. Improvement rates were 40% at week 4, 72% at week 12, 80% at week 24, and 80% at 1-2-years' follow-up, with large effect sizes on fear and PTSD measures. Post-session reduction in fear of earthquakes and increased sense of control over fear at follow-up related to improvement in PTSD.


CONCLUSION
The study provided further evidence of the effectiveness of a single session of behavioural treatment in reducing fear and PTSD in earthquake survivors. Future research needs to examine the usefulness of earthquake simulators in increasing psychological preparedness for earthquakes.