Intervention
CIPE is a 3-week therapist-guided online intervention that was provided via a secure study website. The intervention is based on the prolonged exposure (PE) protocol (Foa, Hembree, Rauch, & Rothbaum, CIPE comprises of four modules that participants sequentially gain access to after completing homework exercises. The modules are text-based and the content is also available as audio files. Participants were informed that the intervention required approximately 6 h per week of their time during the 3-week intervention period. In order to make full use of the short intervention period, the participants were encouraged to have daily contact with their psychologist. To ensure a shared understanding of the intervention components, each module ends with a short quiz of the module content. In the quizzes, the participants are asked to summarise the central intervention component of the specific module. The therapists did not give participants access to the following module until they have been assessed as adhering to the module.Participants could expect to receive a response from their psychologist through an email system within the intervention platform within 24 h on weekdays. The therapists were instructed to guide the participants through the treatment by answering questions, providing support and encouragement on the progress made, and to provide individually tailored feedback on completed assignments, on participants' progress, and/or to troubleshoot eventual difficulties. If a participant did not log in to the platform for 3 days or was late in submitting the homework exercises, the psychologist either sent out reminders via the online platform in the form of short text messages or email, or called the participant by telephone.