Question

McNally, & Robinaugh, & Wu, & Borsboom... (2015) Mental Disorders as Causal Systems: a network approach to PTSD

ABSTRACT>"Debates about posttraumatic stress disorder (PTSD) often turn on whether it is a timeless, cross-culturally valid natural phenomenon or a socially constructed idiom of distress. Most clinicians seem to favor the first view, differing only in whether they conceptualize PTSD as a discrete category or the upper end of a dimension of stress responsiveness. Yet both categorical and dimensional construals presuppose that PTSD symptoms are fallible indicators reflective of an underlying, latent variable. This presupposition has governed psychopathology research for decades, but it rests on problematic psychometric premises. In this article, we review an alternative, network perspective for conceptualizing mental disorders as causal systems of interacting symptoms, and we illustrate this perspective via analyses of PTSD symptoms reported by survivors of the Wenchuan earthquake in China. Finally, we foreshadow emerging computational methods that may disclose the causal structure of mental disorders."

Question:

I am needing help understanding the abstract. Perhaps it would make better sense if I could understand the meaning of "latent variable" and then perhaps I can interpret the limitations of latent variable approaches?

Answer 1

A latent variable is one which is hidden and cannot be observed directly. Intelligence, for example is a latent variable because we cannot observe it directly but only measure it indirectly through the use of tests. In this study, the researchers argue that different theories that explain PTSD (such as the categorical or dimensional approach) understand the disorder symptoms as a single, hidden variable. However, they want to challenge this idea by analysing another perspective, which views mental disorders in terms of interacting symptoms.