This is a study to compare the efficacy and response pattern of a trauma focused CBT modality, brief eclectic psychotherapy for PTSD, with EMDR.
Basically, it shows that with EMDR the PTSD scale drops 40 points, whereas with trauma focused CBT (BET) it takes 17 sessions to get the same results.
I think it is important to consider that the point isn’t to stop EMDR after 6 sessions because the PTSD scale has dropped but instead to keep doing therapy working on related issues. Because of the reduction in PTSD symptoms, the therapist and client can use the time to help the client get caught up on developmental issues that may have been delayed due to the years of PTSD.