Evaluating the Effectiveness of Complex, Multi-component, Dynamic, Community-Based Injury Prevention Interventions: A Statistical Framework.

Dynamic violence and injury prevention interventions located within community settings raise evaluation challenges by virtue of their complex structure, focus, and aims. They try to address many risk factors simultaneously, are often overlapped in their implementation, and their implementation may be phased over time. This article proposes a statistical and analytic framework for evaluating the effectiveness of multilevel, multisystem, multi-component, community-driven, dynamic interventions. The proposed framework builds on meta regression methodology and recently proposed approaches for pooling results from multi-component intervention studies. The methodology is applied to the evaluation of the effectiveness of South African community-centered injury prevention and safety promotion interventions. The proposed framework allows for complex interventions to be disaggregated into their constituent parts in order to extract their specific effects. The potential utility of the framework is successfully illustrated using contact crime data from select police stations in Johannesburg. The proposed framework and statistical guidelines proved to be useful to study the effectiveness of complex, dynamic, community-based interventions as a whole and of their components. The framework may help researchers and policy makers to adopt and study a specific methodology for evaluating the effectiveness of complex intervention programs.

Trauma exposure, posttraumatic stress disorder and the effect of explanatory variables in paramedic trainees.

BACKGROUND: Emergency healthcare workers, including trainees and individuals in related occupations are at heightened risk of developing posttraumatic stress disorder (PTSD) and depression owing to work-related stressors.We aimed to investigate the type, frequency, and severity of direct trauma exposure, posttraumatic stress symptoms and other psychopathology amongst paramedic trainees. In order to create a risk profile for individuals who are at higher occupational risk of developing PTSD, we examined risk and resilience factors that possibly contributed to the presence and severity of posttraumatic symptomatology. METHODS: Paramedic trainees (n = 131) were recruited from a local university. A logistic regression analysis was conducted using the explanatory variables age, gender, population group, trauma exposure, depression, alcohol abuse, alcohol dependence, resilience and social support. RESULTS: 94% of paramedic trainees had directly experienced trauma, with 16% meeting PTSD criteria. A high rate of depression (28%), alcohol abuse (23%) and chronic perceived stress (7%) and low levels of social support was found. The number of previous trauma exposures, depression, resilience and social support significantly predicted PTSD status and depression had a mediating effect. CONCLUSION: There is a need for efficient, ongoing screening of depressive and PTSD symptomatology in trauma exposed high risk groups so that early psychological supportive interventions can be offered.