[gov3009-l] VanderWeele on "A marginal structural model for loneliness"

Hi all, We hope that you can join us for the Applied Statistics Workshop this Wednesday, November 10th when we will be happy to have Tyler VanderWeele from the Harvard School of Public Health. You will find an abstract below. As always, we will serve a light lunch (sandwiches) and the talk will begin around 12:15p. “A marginal structural model for loneliness: implications for clinical trials?” Tyler VanderWeele Harvard School of Public Health CGIS K354 (1737 Cambridge St.) Wednesday, November 10th, 12 noon Abstract: Clinical scientists, policy makers, and individuals must make decisions concerning effective interventions that address health-related issues. We use longitudinal data on loneliness and depressive symptoms and a class of causal models to illustrate how empirical evidence can be used to inform intervention trial design and clinical practice. Data were obtained from a population-based study of non-Hispanic Caucasians, African Americans and Latino Americans born between 1935 and 1952. Marginal structural causal models were employed to evaluate the extent to which depressive symptoms depend not only on loneliness measured at a single point in time (as in prior studies of the effect of loneliness) but also on an individual?s entire loneliness history. Our results indicate that if interventions to reduce loneliness by one standard deviation were made one and two years prior to assessing depressive symptoms, both would have an effect and would together result in an average reduction in depressive symptoms of 0.33 standard deviations (95% CI: 0.21, 0.44, P<0.0001). In light of the persistence of the effects of loneliness, our results also suggests that, in the evaluation of interventions on loneliness, it may be important to allow for a considerable follow-up period in assessing outcomes. Cheers, matt. ~~~~~~~~~~~ Matthew Blackwell PhD Candidate Institute for Quantitative Social Science Department of Government Harvard University url: http://people.fas.harvard.edu/~blackwel/