American Journal of Public Health December Issue research highlights:

TBI laws effective at reducing rate of recurrent concussions among high school athletes

Newswise — This study examined the trends of new and recurrent sports-related concussions in high school athletes before and after traumatic brain injury laws were implemented. Researchers observed significantly increased trends of reported new and recurrent concussions from the time period before the law was implemented through the postlaw period. The study authors explain that this rise in concussions can be attributed to increased identification and reporting.

However, the recurrent concussion rate showed a significant decline 2.6 years after the laws went into effect. Researchers suggest that this decline could be ascribed to removal and return-to-play requirements, indicating that TBI laws may have an effect on reducing negative public health outcomes.

["New and recurrent concussions in high-school athletes before and after traumatic brain injury laws, 2005-2016." Contact: Jingzhen Yang, Center for Injury Research and Policy, The Research Institute at Nationwide Children’s Hospital and Department of Pediatrics, Columbus, OH].

“Shall-issue” gun permit laws significantly associated with higher firearm homicide rates

This study examined the relation of “shall-issue” laws, in which permits must be issued if requisite criteria are met, and “may-issue” laws, which give law enforcement officials wide discretion over whether to issue concealed firearm carry permits or not; and their impact on homicide rates. Researchers compared data from 50 states during the 25-year period of 1991 to 2015.

Researchers found that shall-issue laws were significantly associated with 6.5% higher total homicide rates, 8.6% higher firearm homicide rates, and 10.6% higher handgun homicide rates. This study suggests that there is a robust association between shall-issue laws and higher rates of firearm homicides.

["Easiness of legal access to concealed firearm permits and homicide rates in the United States." Contact: Michael Siegel, MD, MPH Department of Community Health Sciences, Boston University School of Public Health, Boston, MA].

How many US adults carry loaded handguns?

Researchers surveyed a group of handgun owners in 2015 and asked about their carrying behavior over the last 30 days.  The study found that of surveyed handgun owners, 24% carried loaded handguns monthly, of whom 35% did so daily. 82% carried primarily for protection. The proportion of handgun owners who carried concealed loaded handguns in the past 30 days was 21%  in unrestricted states, 25% in shall issue (no discretion) states, 20% in shall issue (limited discretion) states, and 9% in may-issue states.

Researchers estimate that 9 million US adult handgun owners carry loaded handguns monthly, 3 million do so every day, and most report protection as the main carrying reason. Proportionally fewer handgun owners carry concealed loaded handguns in states that allow issuing authorities substantial discretion in granting carrying permits.

[“Loaded handgun carrying among us adults, 2015.” Contact: Ali Rowhani-Rahbar, Department of Epidemiology, School of Public Health, and Harborview Injury Prevention & Research Center, University of Washington, Seattle, WA].

Changes in prevalence of abortion 2008-2014

This study found that between 2008 and 2014, the abortion rate declined 25% among women aged 15 to 44 years. The abortion rate for adolescents aged 15 to 19 years declined 46%, the largest of any group. Abortion rates declined for all racial and ethnic groups but were larger for non-White women than for non-Hispanic White women. Although the abortion rate decreased 26% for women with incomes less than 100% of the federal poverty level, this population had the highest abortion rate of all the groups examined: 36.6. If the 2014 age-specific abortion rates prevail, 24% of women aged 15 to 44 years in that year will have an abortion by age 45 years.

Researchers concluded that the decline in abortion from 2008-2014 was not uniform across all population groups. In their discussion, study authors point to recent research suggesting changes in contraception use are a factor in declining abortion rates.

[“Population group abortion rates and lifetime incidence of abortion: United States, 2008–2014.” Contact: Rachel K. Jones, Guttmacher Institute, New York, NY].

Find a full list of AJPH research papers published online below:

  • Randomized effectiveness trial of a school-based curriculum to improve depression literacy among US secondary school students
  • Changes in population group abortion rates between 2008 and 2014 and lifetime incidence of abortion
  • The effectiveness of HIV prevention interventions in socioeconomically disadvantaged ethnic minority women: a systematic review and meta-analysis.
  • Integrating HIV surveillance and field services: data quality and care continuum in king county (WA), 2010-2015
  • Shade sail effect on use of recreation areas in public parks of Melbourne and Denver: a randomized intervention
  • A community-level prepackaged food sodium reduction intervention in Boston, 2013-2015
  • Trends of new and recurrent concussions in high school athletes before and after TBI laws, 2005-2016
  • The cumulative probability of arrest by age 28 by disability status, race, and gender
  • A 21st century public health approach to abortion
  • Text messaging for improving art adherence: no effects after one year in a randomized controlled trial among adolescents
  • Integrating HIV pre-exposure prophylaxis (prep) into routine preventive healthcare to avoid exacerbating disparities
  • Geographic analysis of scorpion exposures reported to us poison control centers from 2010 to 2015
  • Trends in daily cannabis use among cigarette smokers in the united states, 2002-2014
  • State concealed firearm carrying laws and homicide rates in the US
  • Community health workers in the united states: challenges in identifying, surveying, and supporting the workforce
  • Loaded handgun carrying among adult handgun owners in the united states: results of a national survey

The articles above will be published online October 19, 2017, at 4 p.m. EDT by AJPH under “First Look.” “First Look” articles have undergone peer review, copyediting and approval by authors but have not yet been printed to paper or posted online by issue. AJPH is published by the American Public Health Association, and is available at

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