Preliminary evidence suggests that neighborhood environments, such as socioeconomic disadvantage, pedestrian and physical activity infrastructure, and availability of neighborhood destinations (e.g., parks), may be associated with late-life cognitive functioning and risk of Alzheimer’s disease and related disorders (ADRD). The supposition is that these neighborhood characteristics are associated with factors such as mental health, environmental exposures, health behaviors, and social determinants of health that in turn promote or diminish cognitive reserve and resilience in later life. However, observed associations may be biased by self-selection or reverse causation, such as when individuals with better cognition move to denser neighborhoods because they prefer many destinations within walking distance of home, or when individuals with deteriorating health choose residences offering health services in neighborhoods in rural or suburban areas (e.g., assisted living). Research on neighborhood environments and ADRD has typically focused on late-life brain health outcomes, which makes it difficult to disentangle true associations from associations that result from reverse causality. In this paper, we review study designs and methods to help reduce bias due to reverse causality and self-selection, while drawing attention to the unique aspects of these approaches when conducting research on neighborhoods and brain aging.

“Resiliency” for communities at risk from sea level rise and its effects means preserving as much property and associated economic activity as possible without disrupting current activity or expending funds on projects that provide limited long-term utility or social value. Of interest is how the coincidence of these events impacts the need for storm water improvements and the financial obligations they will entail. This research project focused on the impacts of a non-coastal, groundwater influenced southeast Florida community and the long-term funding they will need to reduce flooding in the community using GIS. This research involved defining surface elevations and groundwater levels, assessing the impacts of sea level rise on groundwater, assessing impacts to storm water from rainfall, identifying likely improvements, and assessing the scale for improvements. The analysis used three extreme rainstorm events under the 0-, 1-, 2-, and 3-foot sea level rise scenarios to determine the magnitude of the cost of the improvements. For a 35-square mile community, our research estimated that the cost could exceed $300 million. For a community not directly adjacent to the coast, the magnitude of these costs should be of interest to similarly placed communities.

Diversifying racial and ethnic participation in clinical research contributes to the generalizability of findings. Yet minority populations remain underrepresented, presenting challenges for studies targeting diverse undergraduate student populations. The researchers of a randomized controlled trial (RCT) explored a recruitment methodology including peer engagement. This article reports on the methodology and outcomes of a peer-to-peer (“Student Ambassador”) recruitment strategy alongside other approaches (email, digital advertising). To understand (1) how peer engagement can diversify student recruitment efforts, the researchers examined descriptive statistics and responses from the baseline and follow-up surveys of the RCT. To understand (2) how Student Ambassadors experienced engagement, the researchers convened a focus group. While a causal relationship is not asserted, we found that study participation approximately represented the student population in terms of ethnic and racial background. Among recruitment approaches, some appeared better aligned with individual ethnic and racial groups. Nine percent of participants reported hearing about the study from peer-to-peer activities (Ambassador engagement, social media, or word-of-mouth), making such approaches a valuable reinforcement of other methods. The diverse team of Student Ambassadors reported job satisfaction, citing interactivity and relatability as success factors. We conclude that diversifying recruitment methods in alignment with target populations may enhance research results. In addition, peer-to-peer methods can expose underrepresented groups to the research process.