During treatment , participants receiving prolonged exposure demonstrated greater improvement on the PTSD symptom severity scale ( difference between treatments in improvement , 7.5 ; 95 % CI , 2.5-12 .5 ; P < .001 ) and on all secondary outcomes ( loss of PTSD diagnosis : difference , 29.3 % , 95 % CI , 20.2 % -41.2 % ; P = .01 ; self-reported PTSD severity : difference , 6.2 ; 95 % CI , 1.2-11 .2 ; P = .02 ; depression : difference , 4.9 ; 95 % CI , 1.6-8 .2 ; P = .008 ; global functioning : difference , 10.1 ; 95 % CI , 3.4-16 .8 ; P = .008 ) .