Predicting Latent Class Scores for Subsequent Analysis

Latent class regression models relate covariates and latent constructs such as psychiatric disorders. Though full maximum likelihood estimation is available, estimation is often in three steps: (i) a latent class model is fitted without covariates; (ii) latent class scores are predicted; and (iii) the scores are regressed on covariates. We propose a new method for predicting class scores that, in contrast to posterior probability-based methods, yields consistent estimators of the parameters in the third step. Additionally, in simulation studies the new methodology exhibited only a minor loss of efficiency. Finally, the new and the posterior probability-based methods are compared in an analysis of mobility/exercise.     

POST-TRAUMATIC STRESS REACTIONS AMONGST RESCUE WORKERS AFTER A MAJOR RAIL ACCIDENT

Abstract

Rescue tasks under heavy strain may act as traumatic events creating stress reactions among the rescue workers. After a major rail accident the rescue workers were examined by questionnaire at 3 and 7 months postaccident using the General Health Questionnaire-28 (GHQ), Impact of Event Scale (IES) and a structured questionnaire made for the purpose. Eighteen percent of the 77 rescue workers who participated in the study had GHQ-case-score and 10% had IES-case-score at 7 months using the usual GHQ-cut-off (4/5) and a low IES-cut-off (19/20). For the case-scorers there was a tendency towards increased GHQ- and IES-scores from 3 to 7 months. Five (6%) had post-traumatic stress disorders (PTSD) of low to moderate severity at 7 months.     

Beyond the Individual: Promoting Mental and Behavioural Health in Low- and Middle-income Countries

This brief report describes a programmatic approach to health promotion that can help address the social determinants of mental-health and associated risky behaviours. Using a South African case example, we illustrate that while micro-system interventions help to strengthen individual resilience and immediate proximal protective influences, group system interventions can assist to promote health enhancing social identities and representations. We conclude that multi-level interventions that assume a systemic focus can strengthen community transformative efforts to address social determinants of mental and behavioural health.     

Mechanisms of change in cognitive behaviour therapy for panic disorder: The role of panic self-efficacy and catastrophic misinterpretations

The efficacy of cognitive behavioural therapy (CBT) for panic disorder with or without agoraphobia (PD) is well-established; however, little is known about the underlying change processes of clinical improvement during therapy. According to cognitive theories, CBT for PD primarily works by changing catastrophic misinterpretations of bodily symptoms and panic attacks. However, panic self-efficacy, i.e. the perceived ability to cope with panic attacks, has also been suggested as an important change mechanism in CBT for PD. The aim of the study was to investigate if change in catastrophic misinterpretations and panic self-efficacy mediated change in the level of anxiety during the course of thirteen sessions of group CBT for PD. Forty-five participants completed weekly self-report measures of the possible cognitive mediators and the level of anxiety throughout therapy. The results indicated that within-person change in panic self-efficacy in one session, but not in catastrophic misinterpretations, predicted within-person level of anxiety symptoms the following week. However, in a reversed analysis, prior change in level of anxiety symptoms also predicted change in panic self-efficacy the following session. These results support panic self-efficacy as a mediator of change in CBT for PD, although a reciprocal causal relationship between panic self-efficacy and level of anxiety seems to be implied.     

From Euler to Navier–Stokes: A Spatial Analysis of Conceptual Changes in Nineteenth-century Fluid Dynamics

This article provides a spatial analysis of the conceptual framework of fluid dynamics during the nineteenth century, focusing on the transition from the Euler equation to the Navier–Stokes equation. A dynamic version of Peter Gärdenfors's theory of conceptual spaces is applied which distinguishes changes of five types: addition and deletion of special laws; change of metric; change in importance; change in separability; addition and deletion of dimensions. The case instantiates all types but the deletion of dimensions. We also provide a new view upon limiting case reduction at the conceptual level that clarifies the relation between the predecessor and successor conceptual framework. The nineteenth-century development of fluid dynamics is argued to be an instance of normal science development.     

UNCERTAINTY AND GOD: A JAMESIAN PRAGMATIST APPROACH TO UNCERTAINTY AND IGNORANCE IN SCIENCE AND RELIGION

This article picks up from William James's pragmatism and metaphysics of experience, as expressed in his “radical empiricism,” and further develops this Jamesian pragmatist approach to uncertainty and ignorance by connecting it to phenomenological thought. The Jamesian pragmatist approach avoids both a “crude naturalism” and an “absolutist rationalism,” and allows for identification of intimations of the sacred in both scientific and religious practices—which all, in their respective ways, try to make sense of a complex world. Analogous to religious practices, emotion and the metaphysics of experience play a central role in science, especially the emotion of wonder. Engaging in scientific or religious practices may create opportunities for individuals to realize that they are co‐creators of the world in partnership with God, in full awareness of uncertainty and ignorance and filled with the emotion of wonder.