Although participants in the mindfulness-based stress reduction group were more likely to show clinically significant improvement in self-reported PTSD symptom severity ( @ % vs @ % with present-centered group therapy ; difference , @ % ; @ % CI , @ % -@ % ; P = @ ) at @-month follow-up , they were no more likely to have loss of PTSD diagnosis ( @ % vs @ % , respectively ; difference , @ % ; @ % CI , -@ % to @ % ; P = @ ) .