FORAS

The course that symptoms take with people experiencing post-traumatic stress disorder (PTSD) differs widely. Most trauma-exposed individuals are  either resilient or quickly recovering from initial symptoms, while for a subgroup of individuals PTSD symptoms are severe and may persist for years. However, the way these trajectories are defined and applied in the research vary widely, which makes systematic analysis more complicated. The goal of the FORAS project is to create a unified framework of the different trajectories the PTSD symptoms of a person who experienced a traumatic event can take. FORAS stands for Framework for PTSS trajectORies: Analysis and Synthesis.

Progress

FORAS consists of three sub-projects to address the different steps necessary to develop this framework.

Part 1: The Hunt for the Last Relevant Paper

To arrive at a unified framework of PTSD trajectories, we needed to update and expand upon a previous systematic literature review on PTSD trajectories following traumatic events. For FORAS to truly consolidate the definitions used in this diverse and global academic field, we wanted to make sure we included every single last paper that met the inclusion criteria for our systematic review; and so the Hunt for the Last Relevant Paper was born.

The conceptual question central to this sub-project is whether it is possible to find every last relevant paper in a field, within a reasonable amount of time and with finite resources. Essentially, you would need to cast as wide a net as possible and sift through the vast amount of results while balancing efficiency and precision. We launched an investigation to test what strategy would work best to have the most chance at finding your last relevant paper.

In the study, we compared different screening strategies; manual screening, active learning with ASReview, and a hybrid approach that combines both. We also explored what stopping rules might be realistic if you’re trying to truly find every last relevant record. While the hybrid screening strategy did not necessarily outperform other methods in identifying more relevant papers, it did result in higher satisfaction and trust among reviewers, and the reviewing process was perceived as more enjoyable. The findings suggest that a hybrid human-AI approach can be a practical and trustworthy tool to improve systematic review processes, especially when the goal is to exhaustively identify relevant literature.

Output 1st study

Pre-print
Data&codebook
Scripts

Part 2: Prevalence of PTSD Symptom Trajectories Following Trauma

This second study in the FORAS project focuses on understanding the different trajectories PTSD symptoms can take following exposure to traumatic events. Using insights from the literature identified in the Hunt for the Last Relevant Paper, we performed a comprehensive systematic review of longitudinal studies of PTSD symptom trajectories following potentially traumatic events. We included all currently published studies that used ‘growth mixture modeling’ approaches, which can be used to find different groups of people based on their symptom severity and symptom change over time after trauma. Within these studies, we then estimated the occurrence rates of the most common PTSD symptom trajectories: low symptomatic, recovery, worsening, high symptomatic and partially symptomatic. We also investigated potential socio-demographic, trauma-related and methodological moderators of these occurrence rates.

The 90 included studies showed inconsistencies in how their observed trajectories were defined and operationalized. To address this, we performed a conceptual analysis of the included studies on PTSD trajectories, identifying how authors defined trajectories and how those definitions matched their analytical approaches. We then developed a standardized framework for trajectory classification that includes clear definitions and visualizations, grounded in both theory and empirical research..

The framework supports both conceptual clarity and practical application, helping researchers and clinicians distinguish among PTSD symptom patterns following trauma and improving consistency across current and future studies.

Output 2nd study

Pre-print
Data
Scripts

Part 3: Occurrence and Prevalence of Latent Class Trajectories of Posttraumatic Stress Symptoms in Clinical Cases

The third study we perform a systematic review and meta-analysis to identify common latent groups or classes of PTSD trajectories of clinical samples specifically. Clinical samples vary substantially from the population level data used in the second study, which mean the applicability of the trajectories defined there will likely differ too. The data in the second study encompasses people who were exposed to a traumatic event, regardless of whether they were at some point clinically diagnosed with PTSD. The data for this study, the subjects are all diagnosed with clinical PTSD. This paper studies the prevalence of the different trajectories in a clinical setting and identify predictors to better understand how and under what circumstances clinical PTSD presentations may develop.

Funding

The FORAS project was funded by the Dutch Research Council - Domain Social Sciences and Humanities (SSH), under File no. 406.22.GO.048.

People involved