Do traditional economic theories of free riding behavior explain spatial clustering of HPV vaccine uptake?

RATIONALE: Geographic clusters of low vaccination uptake reduce the population-level efficacy of vaccination programs. However, little is known about the mechanisms that drive geographic patterns in vaccination rates. Traditional economic theory considers vaccination as a classic public good and suggests that free riding-individuals taking advantage of public goods by relying on others' immunization behavior without contributing toward them-is a primary cause of low vaccination rates. However, behavioral economics suggests that free riding does not fully explain observed individual behavior, and the presence of both high and low clusters of vaccination rates suggest that this theory alone does not fully explain geographic patterns of vaccination. OBJECTIVE: We assessed geographic clustering of HPV vaccination uptake and examined the evidence for or against free riding in HPV vaccination decisions. METHODS: We analyzed HPV vaccination decisions of low-income adolescent females (N = 601) residing in urban neighborhoods in Dallas, Texas, USA during 2011-2012. Spatial econometric models were estimated to assess the relationship between neighborhood vaccination rates and individual vaccination decisions. RESULTS: We found a positive and significant relationship between individual HPV vaccination choices and the average neighborhood vaccination rate at the time parents were making vaccine decisions for their adolescent daughters while controlling for neighborhood sorting and other confounders. CONCLUSION: Individuals were more likely to complete the HPV vaccination series when others in their neighborhood had already completed the series. We do not find evidence for free riding in HPV vaccination decisions.

Physical activity counseling in primary care: Insights from public health and behavioral economics.

Physical inactivity has reached epidemic proportions in modern society. Abundant evidence points to a causal link between physical inactivity and increased risk for numerous noncommunicable diseases, such as some types of cancer and heart disease, as well as premature mortality. Yet, despite this overwhelming evidence, many individuals do not meet the recommended amount of physical activity required to achieve maximum health benefits. Because primary care physicians' advice is highly regarded, clinicians have the unique opportunity to play an important role in enabling patients to modify their behavior at the point of care with the goal of guiding patients to adopt and maintain an active lifestyle. In the current study, the authors evaluate pertinent literature from the fields of medicine/public health and economics/psychology to suggest a comprehensive approach to physical activity counseling at the primary care level. They first examine the public health approach to physical activity counseling, and then proceed to offer insights from behavioral economics, an emerging field that combines principles from psychology and economics. The application of key behavioral economics tools (eg, precommitment contracts, framing) to physical activity counseling in primary care is elaborated. CA Cancer J Clin 2017;67:233-244. © 2017 American Cancer Society.

Multiple Comorbidities and Interest in Research Participation Among Clients of a Nonprofit Food Distribution Site.

BACKGROUND: Persons accessing food from nonprofit distribution sites face numerous challenges and typically have significant unmet health needs. However, given limited and intermittent healthcare system engagement, this vulnerable population is underrepresented in clinical research. We sought to better understand the health needs of a nonclinical population to inform future research and interventions. METHODS: Focus groups were conducted in English (n = 4) and Spanish (n = 4) with clients of Crossroads Community Services (CCS), the largest distributor of North Texas Food Bank. Discussions probed participants' health status, healthcare utilization, understanding and utilization of mammography, and attitudes toward participation in research. RESULTS: Participants included 42 CCS clients, primarily Hispanic or African American women. Participants reported multiple comorbid conditions among household members, yet utilization of health services was often limited by cost. The majority expressed interest in participating in research to communicate their health concerns and obtain emotional support. CONCLUSION: CCS clients represent a high-need, under-reached population willing to engage in health-related research that affords them opportunity to connect with peers in group settings and obtain information to improve management of daily life challenges. The Community Assistance Research (CARe) Initiative, a community-academic collaboration, establishes a much-needed opportunity for ongoing clinical research and intervention among this underserved population.

Neighborhood effects in a behavioral randomized controlled trial.

Randomized controlled trials (RCTs) of interventions intended to modify health behaviors may be influenced by neighborhood effects which can impede unbiased estimation of intervention effects. Examining a RCT designed to increase colorectal cancer (CRC) screening (N=5628), we found statistically significant neighborhood effects: average CRC test use among neighboring study participants was significantly and positively associated with individual patient's CRC test use. This potentially important spatially-varying covariate has not previously been considered in a RCT. Our results suggest that future RCTs of health behavior interventions should assess potential social interactions between participants, which may cause intervention arm contamination and may bias effect size estimation.

Neighborhood-level socioeconomic deprivation predicts weight gain in a multi-ethnic population: longitudinal data from the Dallas Heart Study.

OBJECTIVE: The aim of this study is to examine a relationship between neighborhood-level socioeconomic deprivation and weight change in a multi-ethnic cohort from Dallas County, Texas and whether behavioral/psychosocial factors attenuate the relationship. METHODS: Non-movers (those in the same neighborhood throughout the study period) aged 18-65 (N=939) in Dallas Heart Study (DHS) underwent weight measurements between 2000 and 2009 (median 7-year follow-up). Geocoded home addresses defined block groups; a neighborhood deprivation index (NDI) was created (higher NDI=greater deprivation). Multi-level modeling determined weight change relative to NDI. Model fit improvement was examined with adding physical activity and neighborhood environment perceptions (higher score=more unfavorable perceptions) as covariates. A significant interaction between residence length and NDI was found (p-interaction=0.04); results were stratified by median residence length (11 years). RESULTS: Adjusting for age, sex, race/ethnicity, smoking, and education/income, those who lived in neighborhood >11 years gained 1.0 kg per one-unit increment of NDI (p=0.03), or 6 kg for those in highest NDI tertile compared with those in the lowest tertile. Physical activity improved model fit; NDI remained associated with weight gain after adjustment for physical activity and neighborhood environment perceptions. There was no significant relationship between NDI and weight change for those in their neighborhood ≤11 years. CONCLUSIONS: Living in more socioeconomically deprived neighborhoods over a longer time period was associated with weight gain in DHS.

Physicians, clinics, and neighborhoods: multiple levels of influence on colorectal cancer screening.

BACKGROUND: We (i) described variability in colorectal cancer (CRC) test use across multiple levels, including physician, clinic, and neighborhood; and (ii) compared the performance of novel cross-classified models versus traditional hierarchical models. METHODS: We examined multilevel variation in CRC test use among patients not up-to-date with screening in a large, urban safety net health system (2011-2012). Outcomes included: (i) fecal occult blood test (FOBT) or (ii) colonoscopy and were ascertained using claims data during a 1-year follow-up. We compared Bayesian (i) cross-classified four-level logistic models nesting patients within separate, nonoverlapping "levels" (physicians, clinics, and census tracts) versus (ii) three hierarchical two-level models using deviance information criterion. Models were adjusted for covariates (patient sociodemographic factors, driving time to clinic, and census tract poverty rate). RESULTS: Of 3,195 patients, 157 (4.9%) completed FOBT and 292 (9.1%) completed colonoscopy during the study year. Patients attended 19 clinics, saw 177 physicians, and resided in 332 census tracts. Significant variability was observed across all levels in both hierarchical and cross-classified models that was unexplained by measured covariates. For colonoscopy, variance was similar across all levels. For FOBT, physicians, followed by clinics, demonstrated the largest variability. Model fit using cross-classified models was superior or similar to 2-level hierarchical models. CONCLUSIONS: Significant and substantial variability was observed across neighborhood, physician, and clinic levels in CRC test use, suggesting the importance of factors at each of these levels on CRC testing. IMPACT: Future multilevel research and intervention should consider the simultaneous influences of multiple levels, including clinic, physician, and neighborhood.