Propensity score prediction for electronic healthcare databases using super learner and high-dimensional propensity score methods

ABSTRACT

The optimal learner for prediction modeling varies depending on the underlying data-generating distribution. Super Learner (SL) is a generic ensemble learning algorithm that uses cross-validation to select among a ‘library’ of candidate prediction models. While SL has been widely studied in a number of settings, it has not been thoroughly evaluated in large electronic healthcare databases that are common in pharmacoepidemiology and comparative effectiveness research. In this study, we applied and evaluated the performance of SL in its ability to predict the propensity score (PS), the conditional probability of treatment assignment given baseline covariates, using three electronic healthcare databases. We considered a library of algorithms that consisted of both nonparametric and parametric models. We also proposed a novel strategy for prediction modeling that combines SL with the high-dimensional propensity score (hdPS) variable selection algorithm. Predictive performance was assessed using three metrics: the negative log-likelihood, area under the curve (AUC), and time complexity. Results showed that the best individual algorithm, in terms of predictive performance, varied across datasets. The SL was able to adapt to the given dataset and optimize predictive performance relative to any individual learner. Combining the SL with the hdPS was the most consistent prediction method and may be promising for PS estimation and prediction modeling in electronic healthcare databases.     

Understanding Community Resilience from a PRA Perspective Using Binary Decision Diagrams

Probabilistic risk assessment (PRA) is a useful tool to assess complex interconnected systems. This article leverages the capabilities of PRA tools developed for industrial and nuclear risk analysis in community resilience evaluations by modeling the food security of a community in terms of its built environment as an integrated system. To this end, we model the performance of Gilroy, CA, a moderate‐size town, with regard to disruptions in its food supply caused by a severe earthquake. The food retailers of Gilroy, along with the electrical power network, water network elements, and bridges are considered as components of a system. Fault and event trees are constructed to model the requirements for continuous food supply to community residents and are analyzed efficiently using binary decision diagrams (BDDs). The study also identifies shortcomings in approximate classical system analysis methods in assessing community resilience. Importance factors are utilized to rank the importance of various factors to the overall risk of food insecurity. Finally, the study considers the impact of various sources of uncertainties in the hazard modeling and performance of infrastructure on food security measures. The methodology can be applicable for any existing critical infrastructure system and has potential extensions to other hazards.     

“Come for the period comics. Stay for the cultural awareness”: reclaiming the troll identity through feminist humor on Reddit’s /r/TrollXChromosomes

/r/TrollXChromosomes is a women-focused humor subreddit on the community site Reddit.com. This essay presents the findings of a thematic content analysis of TrollX’s top-ranked postings. Several themes emerge: that TrollX is a space for networked affective content, that postings often concern women’s embodiment and sexuality, and that they suggest feminist perspectives. These themes are all linked by the image of the troll: a remixed version of the negative, antisocial identity that disrupts and often harasses communities. The TrollX troll invokes a spirit of self-deprecation to revel in the absurdities of life and collectively celebrate women’s everyday experiences. However, this research also argues that the TrollX version of the feminist troll is only partially realized, as it tends to express ambivalence in regards to systemic, intersectional oppression.     

“Friendly” Initiatives: An Emerging Approach to Improve Communities for Vulnerable Populations

A growing number of cities and towns are implementing “friendly” initiatives to change the community’s social and physical infrastructure to address the needs of a particular vulnerable segment of their population. Three prominent examples are aging-friendly, child-friendly, and immigrant-friendly initiatives. Although the limited but growing literature describes these initiatives as promising strategies to improve the quality of life of the targeted population, to date there has been little written about the underlying goals, values, and assumptions of these efforts. Using the value-critical approach, this article aims to better understand these aspects of population-friendly initiatives by examining the scholarly and grey literature. Social workers engaged in community and policy practice can play a key role in these efforts and call attention to the ways they may alleviate or exacerbate inequities. Future research is needed to assess the effects of these initiatives on their targeted population as well as other community residents.     

“Why I Can't Stand Out in Front of My House?”: Street‐Identified Black Youth and Young Adult's Negative Encounters With Police

This street participatory action research (Street PAR) study organized 15 residents to document street‐identified Black youth and adult's negative experiences with police in Wilmington, Delaware. Data were collected on mostly street‐identified Black men and women aged 18–35 in the forms of (1) 520 surveys, (2) 24 individual interviews, (3) four dual interviews, (4) three group interviews, and (5) extensive field observations. Forty‐two percent of survey participants reported being stopped by police in the last year. However, with the exception of being “stopped,” participants overall reported little negative contact with police at least within the past year. Chi‐square and ANOVA analyses suggest an interactional relationship exists between race, gender, and age on experiences with police. Younger Black men (18–21) were found to have the most negative contact with police. Analysis suggests a smaller, more hardened mostly male variant of the larger street community has had repeated contact with police. Qualitative analysis reveals at least two major themes: (1) disrespect and disdain for residents and (2) low motivation for working with police. Street PAR methodology was also found to be instrumental in working with local residents and the Wilmington Police Department to improve conditions between residents and police.     

Coalition for a Healthier Community: Lessons learned and implications for future work

The Coalition for a Healthier Community (CHC) initiative was implemented to improve the health and well-being of women and girls. Underpinning CHC is a gender-based focus that uses a network of community partners working collaboratively to generate relevant behavior change and improved health outcomes. Ten programs are trying to determine whether gender-focused system approaches are cost-effective ways to address health disparities in women and girls. Programs implemented through coalitions made up of academic institutions, public health departments, community-based organizations, and local, regional, and national organizations, are addressing health issues such as domestic violence, cardiovascular disease prevention, physical activity, and healthy eating. Although these programs are ongoing, they have made significant progress. Key factors contributing to their early success include a comprehensive needs assessment, robust coalitions, the diversity of populations targeted, programs based on findings of the needs assessments, evaluations taking into consideration the effect of gender, and strong academic–community partnerships. A noteworthy impact of these programs has been their ability to shape and impact public, social, and health policies at the state and local levels. However, there have been challenges associated with the implementation of such a complex program. Lessons learned are discussed in this paper.     

“Post-Gay” Yet? The Relevance of the Lesbian and Gay Scene to Same-Sex Attracted Young People in Contemporary Australia

In recent years, the lesbian and gay “scene” of bars, nightclubs, and dance parties has been undergoing a structural decline in many Western cities. This article aimed to examine the relevance of the scene to same-sex attracted young adults amid these changes. An online survey was conducted with 572 same-sex attracted young women and men in Sydney. Only a minority of respondents participated in the scene at least weekly (16%), and the majority did not regard the scene as important to their leisure time (60%). However, respondents valued the scene as a space to connect with other same-sex attracted people and display same-sex affection without fear of hostility. Lesbian and gay identified respondents tended to be more socially engaged with the scene compared to other same-sex attracted respondents. The findings suggest that while the scene continues to be valued by many same-sex attracted young people, improved social attitudes have made participating in the scene less of an imperative.     

中华民族共同体建设视阈下改土归流的历程、原因及作用

明清时期中央王朝实施的改土归流，不仅彻底废除了土司的政治、经济、军事、司法等特权，将国家版图内的人事权、财政权、军事指挥权、行政管理权、文化教育权等悉数收归中央，而且也是中华民族共同体由“自在”向“自觉”过渡的关键环节。明清改土归流经历了一个长期、艰巨、复杂的过程，其中既有土司利益与王朝利益的矛盾、各地土司与辖区民众的矛盾，也有中央王朝通过改土归流以增加税收、朝廷命官与乡村民众要求改土归流等现实动因。改土归流实现了国家“大一统”的目标、凸显明清国家治理能力的进步、加快了中华民族共同体建设的速度。中华民族共同体是一个由政治共同体、经济共同体、文化共同体和社会共同体四者构成的命运共同体。改土归流的实施，不仅是推动共同体由“自在”向“自觉”迈进的关键步骤和重要举措，而且使中华民族共同体在政治、经济、文化和社会诸方面发生巨大变化。     

Using the community of inquiry for interviewing children: theory and practice

Involvement of children in research processes requires various ethical considerations. In particular, while interviewing children, a researcher needs to take into consideration the power imbalance between a researcher and children as well as among children. This article suggests a possible way of mitigating potential risks, drawing on the idea and practice of the Community of Inquiry (CoI) as an interview method. CoI is the practice of group dialog for knowledge-making, where participants talk about a common topic by sharing their lived experiences in a cooperative manner. This article shows that CoI allows children to act as both interviewers and interviewees, which helps children in reflective knowledge-making while at the same time mitigating the ethical concerns of interviewing. To illustrate how CoI can help achieve these goals, this article draws on the empirical research conducted with a group of junior high school students in Japan.     

Does compassion go viral? Social media,caring, and the Fort McMurray wildfire

ABSTRACT

In May 2016, an enormous wildfire threatened the city of Fort McMurray, Alberta and forced the evacuation of all of the city’s residents. Outpourings of support teemed in from all across Canada and over the world, prompting the largest charitable response in Canadian Red Cross history. This paper examines Albertans’ response to the wildfire by exploring caring and helping behaviors as well as the role of social media in facilitating these remarkable charitable efforts. The paper uses mixed methods including an analysis of the most popular Tweets related to the wildfire and an Alberta survey collected months after the disaster. The analysis of tweets reveals that care, concern, and invitations to help were prominent in social media discourse about the wildfire. The analysis of survey data demonstrates that those who followed news about the wildfire on social media express higher overall levels of care and concern for those affected, which led to helping those impacted by the wildfire. The findings provide important insights about the role of social media in disaster relief and recovery as well as citizens’ civic engagement.