Scott Hendricks

Occupational injuries in the mining industry and their association with statewide cold ambient temperatures in the USA.

BACKGROUND Relatively few occupational epidemiological studies have been conducted concerning the association between cold ambient temperatures and cold exposure injuries, and fewer still of traumatic occupational injuries and cold ambient temperatures. METHODS The association of ambient temperature and wind data from the National Climatic Data Center with injury data from mines reported to the Mine Safety and Health Administration (MSHA) was evaluated over a 6 year period from 1985-1990; 72,716 injuries from the seven states with the most numerous injuries were included. Temperature and wind data from each states metropolitan weather stations were averaged for each day of the 6 year period. A weighted linear regression tested the relationship of ungrouped daily temperature and injury rate for all injury classes. For cold exposure injuries and fall injuries, relative incidence rates for grouped temperature data were fit with Poisson regression. RESULTS As temperatures decreased, injury rates increased for both cold exposure injuries and slip and fall injuries. The association of slip and fall injuries with temperature was inverse but not strictly linear. The strongest association appeared with temperatures 29 degrees F and below. The injury rates for other accident categories increased with increasing ambient temperatures. CONCLUSIONS This study suggests that statewide average ambient temperature reflects the expected association between the thermal environment and cold exposure injuries for workers, but more importantly, documents an association between ambient temperatures and occupational slip and fall injuries.

Suicide in U.S. workplaces, 2003-2010: a comparison with non-workplace suicides

INTRODUCTION Suicide rates have risen considerably in recent years. National workplace suicide trends have not been well documented. The aim of this study is to describe suicides occurring in U.S. workplaces and compare them to suicides occurring outside of the workplace between 2003 and 2010. METHODS Suicide data originated from the Census of Fatal Occupational Injury database and the Web-Based Injury Statistics Query and Reporting System. Suicide rates were calculated using denominators from the 2013 Current Population Survey and 2000 U.S. population census. Suicide rates were compared among demographic groups with rate ratios and 95% CIs. Suicide rates were calculated and compared among occupations. Linear regression, adjusting for serial correlation, was used to analyze temporal trends. Analyses were conducted in 2013-2014. RESULTS Between 2003 and 2010, a total of 1,719 people died by suicide in the workplace. Workplace suicide rates generally decreased until 2007 and then sharply increased (p=0.035). This is in contrast with non-workplace suicides, which increased over the study period (p=0.025). Workplace suicide rates were highest for men (2.7 per 1,000,000); workers aged 65-74 years (2.4 per 1,000,000); those in protective service occupations (5.3 per 1,000,000); and those in farming, fishing, and forestry (5.1 per 1,000,000). CONCLUSIONS The upward trend of suicides in the workplace underscores the need for additional research to understand occupation-specific risk factors and develop evidence-based programs that can be implemented in the workplace.

Convenience store robberies in selected metropolitan areas. Risk factors for employee injury.

Circumstances of injury were abstracted from police reports for 1835 convenience store robberies that occurred during 1992 or 1993 in selected metropolitan areas of seven eastern states. Subset analyses were performed using the data (758 robberies) from four states with relatively complete risk factor information. The purpose of this study was to estimate the risk of injury in a robbery situation for various risk factors. The overall risk of employee robbery-related injury could not be estimated because the probability of robbery is unknown. Of the 1835 robberies, 59% of the total robberies occurred at nighttime (9 p.m. to 3 a.m.), 47% occurred in stores previously robbed in the study period, 63% involved the use of a firearm, and 12% were associated with an injury to at least one employee. In the subset analysis of 758 robberies in four states, the employee probability of injury in a robbery was lower with firearm use compared with no weapon or use of a blunt instrument, and the probability of severe injury (defined as death, or an injury necessitating a trip to a hospital) was lower with a firearm compared with the use of a blunt instrument. However, all five fatalities were firearm-related. Other factors that were associated with a lower probability of employee injury included robbery occurrence in stores that had been robbed multiple times, compared with stores robbed only once; having 1 to 999 dollars stolen, compared with having no money stolen; and the presence of a customer(s) in the store at the time of the robbery. The employee risk of injury was not significantly different between one- (0.106) and multiple-employee (0.111) stores. Similarly, the employee risk of severe injury was not significantly different between one- (0.029) and multiple-employee stores (0.022). We conclude that there are several potential risk factors for employee injury in convenience store robberies, some of which are amenable to interventions. Further research on these factors and their relationship to employee injury is indicated.

Effectiveness of behavioral safety belt interventions

A wide variety of approaches have been developed to promote safety belt use. This paper evaluates the relationship of types of behavioral safety belt programs to short- and long-term safety belt use rates. Five types of programs were examined: Law, Incentive, Education, Monitoring, and Prompt. Programs were generally effective in increasing use rates, with a median increase of 17.0% (95% CI = 13.4%, 20.1%). Program type differentially affected use rates, with Law and Incentive producing the highest increase in rates. Length of intervention and number of interventions within one program were not significantly related to use rates. Immediately after intervention ended, safety belt use declined but soon stabilized, with rates remaining significantly higher than baseline.

Workplace violence among Pennsylvania education workers: differences among occupations.

PROBLEM The purpose of this study was to measure the prevalence and characteristics of physical and non-physical WPV in a state-based cohort of education workers. METHOD A sample of 6,450 workers was drawn using de-identified union membership lists, stratified on gender, occupation, and school location. A cross-sectional survey was mailed to participants. RESULTS An estimated 7.8% (95%CI=6.6-9.1) of education workers were physically assaulted and 28.9% (95%CI=26.4-31.5) experienced a non-physical WPV event during the 2009-2010 school year. Special education teachers were significantly more likely to be physically assaulted and experience a non-physical WPV event compared to general education teachers (Prevalence Rate Ratio=3.6, 95% 2.4-5.5; PRR=1.4, 95%CI=1.1-1.8). DISCUSSION Special education teachers were at the highest risk for both physical and non-physical WPV. If not already present, schools should consider implementing comprehensive WPV prevention programs for their employees. IMPACT ON INDUSTRY Special education teachers have unique workplace hazards. Strategies that protect the special education teacher, while still protecting the special education student should be considered.

Cigarette Smoking Trends Among U.S. Working Adult by Industry and Occupation: Findings From the 2004–2012 National Health Interview Survey

OBJECTIVE To examine trends in age-adjusted cigarette smoking prevalence among working adults by industry and occupation during 2004-2012, and to project those prevalences and compare them to the 2020 Healthy People objective (TU-1) to reduce cigarette smoking prevalence to ≤12%. METHODS We analyzed the 2004-2012 National Health Interview Survey (NHIS) data. Respondents were aged ≥18 years working in the week prior to the interview. Temporal changes in cigarette smoking prevalence were assessed using logistic regression. We used the regression model to extrapolate to the period 2013-2020. RESULTS Overall, an estimated 19.0% of working adults smoked cigarettes: 22.4% in 2004 to 18.1% in 2012. The largest declines were among workers in the education services (6.5%) industry and in the life, physical, and social science (9.7%) occupations. The smallest declines were among workers in the real estate and rental and leasing (0.9%) industry and the legal (0.4%) occupations. The 2020 projected smoking prevalences in 15 of 21 industry groups and 13 of the 23 occupation groups were greater than the 2020 Healthy People goal. CONCLUSIONS During 2004-2012, smoking prevalence declined in the majority of industry and occupation groups. The decline rate varied by industry and occupation groups. Projections suggest that certain groups may not reach the 2020 Healthy People goal. Consequently, smoking cessation, prevention, and intervention efforts may need to be revised and strengthened, particularly in specific occupational groups.

POWER DETERMINATION FOR GEOGRAPHICALLY CLUSTERED DATA USING GENERALIZED ESTIMATING EQUATIONS

Study designs in public health research often require the estimation of intervention effects that have been applied to a cluster of subjects in a common geographic area, rather than randomly assigned to individual subjects, and where the outcome is dichotomous. Statistical methods that account for the intracluster correlation of measurements must be used or the standard errors of regression coefficients will be under-estimated. Generalized estimating equations (GEE) can be used to account for this correlation, although there are no straightforward methods to determine sample-size requirements for adequate power. A simulation study was performed to calculate power in a GEE model for a proposed study of the effect of an intervention, designed to reduce lower-back injuries among nursing personnel employed in nursing homes. Nursing homes will be randomly assigned to either an intervention or control group and all employees within a nursing home will be treated alike. Historical injury data indicates that the baseline-injury risk for each home can be reasonably modelled using a beta distribution. It is assumed that the risk for any individual nurse within a nursing home follows a Bernoulli probability distribution expressed as a logit function of fixed covariates, which have values of odds ratios determined from previous studies which represent characteristics of the study population, and a random-intercept term which is specific for each home. Results indicate that failure to account for intracluster correlation can lead to overestimates of power as well as inflation of type I error by as much as 20 per cent. Although the GEE method accounted for the intracluster correlation when present, estimates of the intracluster correlation were negatively biased when no intracluster correlation was present. In addition, and possibly related to the negatively biased estimates of intracluster correlation, we also found inflated type I error estimates from the GEE method.

Incidence and risk factors of workplace violence on psychiatric staff

BACKGROUND A study by Hesketh et al. found that 20% of psychiatric nurses were physically assaulted, 43% were threatened with physical assault, and 55% were verbally assaulted at least once during the equivalent of a single work week. From 2005 through 2009, the U.S. Department of Justice reported that mental health occupations had the second highest average annual rate of workplace violence, 21 violent crimes per 1,000 employed persons aged 16 or older. OBJECTIVE An evaluation of risk factors associated with patient aggression towards nursing staff at eight locked psychiatric units. PARTICIPANTS Two-hundred eighty-four nurses in eight acute locked psychiatric units of the Veterans Health Administration throughout the United States between September 2007 and September 2010. METHODS Rates were calculated by dividing the number of incidents by the total number of hours worked by all nurses, then multiplying by 40 (units of incidents per nurse per 40-hour work week). Risk factors associated with these rates were analyzed using generalized estimating equations with a Poisson model. RESULTS Combining the data across all hospitals and weeks, the overall rate was 0.60 for verbal aggression incidents and 0.19 for physical aggression, per nurse per week. For physical incidents, the evening shift (3 pm - 11 pm) demonstrated a significantly higher rate of aggression than the day shift (7 am - 3 pm). Weeks that had a case-mix with a higher percentage of patients with personality disorders were significantly associated with a higher risk of verbal and physical aggression. CONCLUSION Healthcare workers in psychiatric settings are at high risk for aggression from patients.

Changing farm injury trends by sex for youth living on US farms, 1998-2006.

PURPOSE To estimate the number and rate of on-farm injuries to youth living on farms in the United States by sex from 1998 to 2006 and compare the trends in youth injury by sex. METHODS Data from 4 childhood agricultural injury surveys for the years 1998, 2001, 2004, and 2006 were analyzed using a Poisson regression model utilizing generalized estimating equations. Rate ratios with corresponding 95% confidence intervals were calculated from the model, which compared the estimated rates of injury in 2001, 2004, and 2006 to the estimated rate of injury in the baseline year, 1998. RESULTS There was an overall decline in the estimated number and rate of injuries to youth living on farms from 1998 to 2006, with a linear decline of the rate ratios for all youth on farms that was found to be significant. By sex, the trend in injury rate ratios for male youth significantly declined, while the trend for female youth for the same time period initially increased then returned to the baseline. Nonhomogeneity in trends by age group, work versus nonwork injury, and source of injury was also identified. CONCLUSION Additional surveillance is needed to determine if injury trends to youth living on farms will continue to differ by sex. More detailed data on exposure to hazards for these youth by sex are needed to determine what factors are associated with these disparate injury trends and to design and implement effective interventions to further reduce injuries to youth living on farms.

Non-fatal workplace violence injuries in the United States 2003–2004: A follow back study

OBJECTIVE Contribute to the prevention of workplace violence by providing information about the nature and circumstances of nonfatal assaults among U.S. workers. METHODS Data were collected from the National Electronic Injury Surveillance System occupational supplement (NEISS-Work), a stratified probability sample of U.S. hospitals. Workplace violence victims identified from NEISS-Work voluntarily completed a followback interview detailing the nature and circumstances surrounding their workplace violence incident. RESULTS The majority of workplace violence injuries treated in emergency departments resulted from simple assaults that did not involve any lost time from work. Almost two-thirds of these workplace violence victims filed only an internal report. Eighty percent of the victims returned to their same jobs and will not change the way they do their jobs as a result of the violent incident. CONCLUSIONS Nonfatal workplace violence is an important risk for U.S. workers, particularly in some occupations and industries. Prevention strategies need to be tailored by occupation and work environment. Results from the healthcare section of this survey indicate high numbers of incidents during times when the healthcare workers were assisting patients with medical and non-medical needs.