A randomised controlled trial of therapist-assisted online psychological therapies for posttraumatic stress disorder (STOP-PTSD): trial protocol

BACKGROUND: Over the last few decades, effective psychological treatments for posttraumatic stress disorder (PTSD) have been developed, but many patients are currently unable to access these treatments. There is initial evidence that therapist-assisted internet-based psychological treatments are effective for PTSD and may help increase access, but it remains unclear which of these treatments work best and are most acceptable to patients. This randomised controlled trial will compare a trauma-focussed and a nontrauma-focussed therapist-assisted cognitive behavioural Internet treatment for PTSD: Internet-delivered cognitive therapy for PTSD (iCT-PTSD) and internet-delivered stress management therapy (iStress-PTSD). METHODS/DESIGN: The study is a single-blind, randomised controlled trial comparing iCT-PTSD, iStress-PTSD and a 13-week wait-list condition, with an embedded process study. Assessors of treatment outcome will be blinded to trial arm. Two hundred and seventeen participants who meet DSM-5 criteria for PTSD will be randomly allocated by a computer programme to iCT-PTSD, iStress-PTSD or wait-list at a 3:3:1 ratio. The primary assessment point is at 13 weeks, and further assessments are taken at 6, 26, 39 and 65 weeks. The primary outcome measure is the severity of PTSD symptoms as measured by the PTSD Checklist for DSM-5 (PCL-5). Secondary measures of PTSD symptoms are the Clinician Administered PTSD Scale for DSM-5 (CAPS-5) and the Impact of Event Scale-Revised (IES-R). Other symptoms and well-being will be assessed with the Patient Health Questionnaire (PHQ-9), Generalised Anxiety Disorder Scale (GAD-7), WHO (Five) Well-Being Index, Work and Social Adjustment Scale (WSAS), Endicott Quality of Life Scale (QoL), and Insomnia Sleep Index (ISI). Health economics analyses will consider quality of life, productivity, health resource utilisation, employment status and state benefits, and treatment delivery costs. Process analyses will investigate candidate mediators and moderators of outcome. Patient experience will be assessed by interview and questionnaire. DISCUSSION: This study will be the first to compare the efficacy of a trauma-focussed and nontrauma-focussed therapist-assisted online cognitive behavioural treatment for people with posttraumatic stress disorder. TRIAL REGISTRATION: ISRCTN16806208. Registered prospectively on 5 January 2018.