Faculty Bibliography

BACKGROUND AND OBJECTIVE/OBJECTIVE:Too little is known about the effectiveness of efforts to prevent firearm violence. Our objective is to evaluate California's Armed and Prohibited Persons System (APPS), a law enforcement intervention that seeks to recover firearms from individuals who purchased them legally but subsequently became prohibited from having access to firearms. Prohibitions usually arise from events suggesting an increased risk for future violence. DESIGN AND STUDY POPULATION/METHODS:This group-randomised trial involves approximately 20 000 APPS-eligible individuals in 1041 communities. Randomisation was performed at the community level, to early or later intervention (Group 1 and Group 2, respectively) with stratification by region, population and violent crime rate. METHODS:APPS is being implemented by the California Department of Justice. The principal outcome measure is the incidence of arrest for a firearm-related or violent crime. Primary analysis will be on an intention-to-treat basis, comparing individuals in Group 1 and Group 2 communities. Analyses will focus on time to event, using proportional hazards regression with adjustment for the clustered nature of the data and incorporating individual- and community-level characteristics. Secondary analyses will examine the effect of the intervention on an as treated basis, effects on subgroups, and effects on community-wide measures such as crime rates. DISCUSSION/CONCLUSIONS:APPS may have a significant impact on risk for future violence among members of its target population. The findings of this study will likely be generalisable and have clear implications for violence prevention policy and practice. TRIAL REGISTRATION NUMBER/BACKGROUND:NCT02318732.

OBJECTIVES/OBJECTIVE:To determine the association of medical marijuana laws (MMLs) with traffic fatality rates. METHODS:Using data from the 1985-2014 Fatality Analysis Reporting System, we examined the association between MMLs and traffic fatalities in multilevel regression models while controlling for contemporaneous secular trends. We examined this association separately for each state enacting MMLs. We also evaluated the association between marijuana dispensaries and traffic fatalities. RESULTS:On average, MML states had lower traffic fatality rates than non-MML states. Medical marijuana laws were associated with immediate reductions in traffic fatalities in those aged 15 to 24 and 25 to 44 years, and with additional yearly gradual reductions in those aged 25 to 44 years. However, state-specific results showed that only 7 states experienced post-MML reductions. Dispensaries were also associated with traffic fatality reductions in those aged 25 to 44 years. CONCLUSIONS:Both MMLs and dispensaries were associated with reductions in traffic fatalities, especially among those aged 25 to 44 years. State-specific analysis showed heterogeneity of the MML-traffic fatalities association, suggesting moderation by other local factors. These findings could influence policy decisions on the enactment or repealing of MMLs and how they are implemented.

The pathways through which neighborhood poverty can affect resident depression are still unknown. We investigated mechanisms through which neighborhood poverty may influence depression among older adults. Participants were drawn from the New York City Neighborhood and Mental Health in the Elderly Study II, a 3-wave study of adults aged 65-75 (n=3,497) at baseline. Neighborhood poverty and homicide were associated with depressive symptoms at follow-up waves (RR:1.20, 95%CI: 1.05, 1.36; RR: 1.09, 95%CI: 1.02, 1.17, respectively). Homicide accounted for 30% of the effect of neighborhood poverty on depressive symptoms. Neighborhood exposure to violence may be a key mechanism through which neighborhood poverty influences depression among older adults.

Neighborhood physical disorder-the visual indications of neighborhood deterioration-may inhibit outdoor physical activity, particularly among older adults. However, few previous studies of the association between neighborhood disorder and physical activity have focused on this sensitive population group, and most have been cross-sectional. We examined the relationship between neighborhood physical disorder and physical activity, measured using the Physical Activity Scale for the Elderly (PASE), in a three-wave longitudinal study of 3497 New York City residents aged 65-75 at baseline weighted to be representative of the older adult population of New York City. We used longitudinal mixed linear regression controlling for a number of individual and neighborhood factors to estimate the association of disorder with PASE score at baseline and change in PASE score over 2 years. There were too few subjects to assess the effect of changes in disorder on activity levels. In multivariable mixed regression models accounting for individual and neighborhood factors; for missing data and for loss to follow-up, each standard deviation increase in neighborhood disorder was associated with an estimated 2.0 units (95% CI 0.3, 3.6) lower PASE score at baseline, or the equivalent of about 6 min of walking per day. However, physical disorder was not related to changes in PASE score over 2 years of follow-up. In this ethnically and socioeconomically diverse population of urban older adults, residents of more disordered neighborhoods were on average less active at baseline. Physical disorder was not associated with changes in overall physical activity over time.

BACKGROUND:Recently, social movements across the world have demanded reforms to education systems and other institutions. Although such movements have affected large numbers of people across multiple countries, we know little about the impacts they have had on population health. We focus on one example: the massive strikes and collective occupation of secondary schools across Chile, which occurred contemporaneously with a large increase in marijuana use among students in this age group. We aimed to evaluate the causal effects that the 2011 Chilean school strikes had on adolescent substance use, including the initiation of marijuana use and the use of alcohol and marijuana. METHODS:School-level, aggregated panel design using data from the National Drug Surveys among Secondary Students from 2005 to 2015 for students in grades 9-12. We used a fixed-effects difference-in-difference model to estimate the effect of school occupations on prevalence of self-reported indicators of drug use. RESULTS:Reported marijuana use doubled between 2009 and 2013 among Chilean adolescents. After controlling for secular trends in outcomes and for school characteristics, there was no evidence of increased marijuana initiation, alcohol and marijuana use, or of an increase in heavy use among adolescents being directly attributable to school strikes and occupations in 2011. CONCLUSIONS:The 2011 Occupy school movement in Chile had no detectable causal effect on substance use among Chilean adolescents. The increase in marijuana use from 2009 to 2013 seems to be part of broader social changes occurring among the school-age population.

OBJECTIVES/OBJECTIVE:To investigate the validity of the apparent downward trend in the national case-fatality rate for gunshot wounds from assault. METHODS:We reanalyzed the estimated annual number of nonfatal firearm injuries the National Electronic Injury Surveillance System reported from 2003 to 2012. We adjusted the estimates for discontinuities created by the substitution of 1 hospital for another in the sample and for a downward trend in the percentage of gunshot injuries classified as "unknown circumstance." Firearm homicide data are from the Centers for Disease Control and Prevention, Web-based Injury Statistics Query and Reporting System. RESULTS:The unadjusted National Electronic Injury Surveillance System estimate increased by 49%, yielding a decline in the case-fatality rate from 25% to 18%. Our adjustments eliminated these trends; the case-fatality rate was 22% in both 2003 and 2012. CONCLUSIONS:With reasonable adjustments, the trend in nonfatal injuries from interpersonal firearms assault tracks the flat trend in firearms homicides, suggesting that there was no increase in firearms violence during this period. The case-fatality rate did not change, and trauma care improvements did not influence the firearms homicide trend.