Two Examples of Public Health Law Research: Methods & FindingsHenry Carretta, PhD, MPH; Colette LeBienvenu; Eli Friedman; Les Beitsch, MD, JD

Department of Behavioral Sciences and Social Medicine, Florida State University College of Medicine, Tallahassee, FL

AbstractTwo studies contrast measurement for Public Health Laws related to two rare health events: 1) pediatric anaphylaxis and 2) infant motor vehicle accident mortality.

1. Complex law mapping with considerable variability between states, health outcomes that are difficult to identify2. Straightforward law mapping with considerable consistency between states and an easily measured outcome. Presentation

elaborates mapping/analytic challenges.

Study 1: Availability and administration of emergency epinephrine in school settings and mortality/morbidity. Considerable variability across states in law organization and details; 250+ laws identified and categorized. Most states have some laws addressing student, school, and employee responsibilities: Student self-carry and administration of medication, School protocols, and employee designation, administration, training and Good Samaritan protections. Identification of health outcome death or hospital visit made difficult by rarity of anaphylactic events; inconsistent death certificate/claims coding.

Study 2: Rear-facing child seat laws (RFCSLs) and infant motor vehicle accident (MVA) fatality. RFCSLs are straightforward, easily found and categorized. Infant RFCSLs use age, weight or both to set requirements. 12 states have passed RFCSLs (2001-2012) specific to infants; little variability in content. Accurate MVA fatality data is available: National Highway Traffic Safety Administration’s Fatality Analysis Reporting System (FARS) database. A state fixed effects model of infant fatalities predicted by state law status and total vehicle miles driven found a 28% reduction in states with RFCSLs. Law status became insignificant when all-age MVA mortality was added.

Public health law mapping and outcome analysis using natural experiment design can be straightforward or complex depending on the law and outcome chosen to be studied.

Availability & Administration of Emergency Epinephrine in Schools

Objective & Motivation •Map state laws legislating the availability & administration of epinephrine in schools

•State laws addressing anaphylaxis in the school setting vary in comprehensiveness

• This may influence school policy on matters such as student self-carry & self-administration of medication,

• Training of personnel in recognition of symptoms,

• Administration of medication to a student by school personnel,

• “Good Samaritan” policies allowing a school to administer medication in good faith.

• Address potential school liability.

Methodology Legislative search using LexisNexis Academic & recorded findings in an Access database. Over 250 pertinent laws were identified and laws were classified into the following categories of to evaluate its comprehensiveness: •Self-Carry of medication, •Self-Administration, •Possession of medication by a school, •Administration of medication by designated employee, •Medical training of designated employees & emergency procedures•Good Samaritan policies for administration of medication in good faith. A legal dataset & interactive law map using the LawAtlas® platform allows for systematic collection, measurement & display of state-level laws. LawAtlas® interactive maps allow users to explore changes in a law over time, differences in laws among states, & key features of each law. Twenty percent of entries are checked by a second reviewer for quality control.

Availability & Administration of Emergency Epinephrine in Schools

Planned Health Outcome Study •Model legislative impact by assessing the likelihood of pediatric anaphylaxis mortality using detailed mortality data from the CDC Division of Vital Statistics (1999-2012)

•Use inpatient & emergency department information for pediatric anaphylaxis hospitalizations using standard state discharge files.

•Mortality & outcome information will be categorized with specificity regarding the location of the incident (on school premises or at a school-related location) & nature of the incident (allergic, anaphylactic, or asthmatic.) using International Classification of Diseases codes (ICD-9-CM & ICD-10) diagnosis & mortality codes

Rear-Facing Child Car Seats & Motor Vehicle Accident Fatality Rates

Objective & Motivation

Examine the impact of state law mandating rear-facing car seats and their effect on infant mortality due to motor vehicle accidents (MVAs):

• MVAs are a leading cause of death in children two years of age & under in the United States.

•The American Academy of Pediatrics (AAP) advised in March 2011 that children should remain in rear facing child car seats until age two, or until they reach the maximum height & weight for their child car seat.

•Through 2012, only 12 states have passed rear-facing care seat legislation for infants.

Methodology

•Identification of statutes via searches in national legal databases for 50 states & DC

•Publicly available, comprehensive MVA fatality data from the National Highway Traffic Safety Administration’s Fatality Analysis Reporting System (FARS) database.

•Longitudinal analysis of legislation enactment & motor vehicle mortality from 1995-2013

•Natural experiment in which infant mortality due to MVAs as the DV for states with & without rear-facing car seat laws

•State fixed effect negative binomial regression to control for unmeasured time invariant state-level factors

Information & Analysis

•12 states passed legislation between 2001 & 2012 (AL, AK, CO, CT, IA, LA, NM, OR, SC, TN, VT, & WI)

•918-state years of data, 77 state-years for states with legislation & 841 state-years for states without legislation

•A two step approach analyzing states with known rear-facing car seat laws:

• Step 1: Descriptive statistics of state vehicle miles driven, number of infant fatalities, number of states with laws, years the laws were prepared and years laws were and were not in place.

• Step 2: Negative binomial count model for infant deaths with state fixed effects

Rear-Facing Child Car Seats & Motor Vehicle Accident Fatality Rates

Principal Findings

•All-age MVA mortality was higher (IRR=2.7) in states with rear-facing child seat laws.

•The model 1 with only state law as a predictor found a protective effect of state law (IRR=0.72) or approximately 28% lower risk of infant mortality in states with rear-facing car seat laws.

•Model 2 included a term that adjusted to all-age MVA mortality rate & law suggests that finding for infant morality in MVAs is driven by overall state mortality rates & that state law was not associated with a statistically significant decline in infant MVA deaths.

Conclusions

•Infant MVA mortality is a rare event. Therefore the study may lack power to detect true differences in mortality. Analysis of MV injuries or injuries and mortality together may be a better approach.

•Unmeasured time-varying factors that may influence the results include: vehicle size and age, driver behaviors, implementation of laws, compliance with laws, law enforcement policies, primary versus secondary enforcement, and positive social norms after passage of laws.

•Examination of weather, highway type, vehicle speed, number of vehicles in the accident, and outcomes for other passengers in MVAs may be revealing.

•Study limitations may have resulted in a more conservative estimate of the impact safer rear-facing car seat laws.

•Further conclusions should wait on additional studies, with longer observation periods, to allow time for the full effects of law implementation to be realized.

•Implementation lag should be specifically modeled.

•High overall state MVA rates was associated with passage of a rear-facing child seat law