Many studies have shown the efficacy of cognitive – behavioral therapy and psychological debriefing in treatment of post traumatic stress disorder (PTSD) and a few evidences are available for using these techniques in large scale disasters.

This study aimed to asses the effect of some psychological interventions in reducing PTSD symptoms after Bam earthquake in different age groups.

In a before-after quasi experimental clinical trial, we compared the efficacy of one session of psychological debriefing and three sessions of group cognitive-behavioral therapy in bam earthquake PTSD symptoms in different age groups. We evaluated PTSD symptoms before and immediately and three months after interventions by CAPS scaling system and analyzed data.

one hundred and thirty persons entered in the study and 51 persons excluded during interventions because of migration. Interventions were showed to be effective only in short term period. The means of PTSD symptoms frequency and severity of avoidance symptoms were reduced during three months period of study which were statistically significant P<0.05. Interventions showed no efficacy for recall symptoms in long term and hyper arousal symptoms in short term and long term periods. There was no statistically significant difference among age groups.

Psychosocial supportive interventions may be effective on some of the PTSD symptoms but there is no difference in different