Background Regular physical activity plays an important role in the amelioration of several mental health disorders; however, its relationship with burnout has not yet been clarified. Objective To determine the association between achievement of national physical activity guidelines and burnout in internal medicine resident physicians. Methods A Web-based survey of internal medicine resident physicians at the University of Minnesota and Hennepin County Medical Center was conducted from September to October 2012. Survey measures included the Maslach Burnout Inventory-Human Services Survey and the International Physical Activity Questionnaire. Results Of 149 eligible residents, 76 (51.0%) completed surveys, which were used in the analysis. Burnout prevalence, determined by the Maslach Burnout Inventory, was 53.9% (41 of 76). Prevalence of failure to achieve US Department of Health and Human Services physical activity guidelines was 40.8% (31 of 76), and 78.9% (60 of 76) of residents reported that their level of physical activity has decreased since they began medical training. Residents who were able to meet physical activity guidelines were less likely to be burned out than their fellow residents (OR, 0.38, 95% CI 0.147–0.99). Conclusions Among internal medicine resident physicians, achievement of national physical activity guidelines appears to be inversely associated with burnout. Given the high national prevalence of burnout and inactivity, additional investigation of this relationship appears warranted.

Breast density is a modifiable factor that is strongly associated with breast cancer risk. We sought to understand the influence of newer technologies of full-field digital mammography (FFDM) on breast density research and to determine whether results are comparable across studies using FFDM and previous studies using traditional film-screen mammography. We studied 24,840 screening-age (40-74 years) non-Hispanic white women who were participants in the Research Program on Genes, Environment and Health of Kaiser Permanente Northern California and underwent screening mammography with either Hologic (Hologic, Inc., Marlborough, Massachusetts) or General Electric (General Electric Company, Boston, Massachusetts) FFDM machines between 2003 and 2013. We estimated the associations of parity, age at first birth, age at menarche, and menopausal status with percent density and dense area as measured by a single radiological technologist using Cumulus software (Canto Software, Inc., San Francisco, California). We found that associations between reproductive factors and mammographic density measured using processed FFDM images were generally similar in magnitude and direction to those from prior studies using film mammography. Estimated associations for both types of FFDM machines were in the same direction. There was some evidence of heterogeneity in the magnitude of the effect sizes by machine type, which we accounted for using random-effects meta-analysis when combining results. Our findings demonstrate the robustness of quantitative mammographic density measurements across FFDM and film mammography platforms.

Background High mammographic density is strongly associated with increased breast cancer risk. Some, but not all, risk factors for breast cancer are also associated with higher mammographic density. Methods The study cohort (N=24,840) was drawn from the Research Program in Genes, Environment and Health of Kaiser Permanente Northern California and included non-Hispanic white females aged 40–74 years with a full-field digital mammogram (FFDM). Percent density (PD) and dense area (DA) were measured by a radiological technologist using Cumulus. The association of age at menarche and late adolescent BMI with PD and DA were modeled using linear regression adjusted for confounders. Results Age at menarche and late adolescent BMI were negatively correlated. Age at menarche was positively associated with PD (p-value for trend<0.0001) and DA (p-value for trend <0.0001) in fully adjusted models. Compared to the reference category of age 12–13 years at menarche, menarche at age >16 years was associated with an increase in PD of 1.47% [95% CI: (0.69, 2.25)] and an increase in DA of 1.59cm2 [95% CI: (0.48, 2.70)]. Late adolescent BMI was inversely associated with PD (p-value <0.0001) and DA (p-value <0.0001) in fully adjusted models. Conclusions Age at menarche and late adolescent BMI are both associated with Cumulus measures of mammographic density on processed FFDM images. Impact Age at menarche and late adolescent BMI may act through different pathways. The long-term effects of age at menarche on cancer risk may be mediated through factors besides mammographic density.

The goal of this study was to compare and contrast the use of personal protective equipment (PPE) and the practice of handwashing among participants of four studies assessing poultry and swine farms in the midwestern United States and in Thailand. This largely descriptive exercise was designed to assess and compare the frequency of these protective practices among the study populations. There were a total of 1113 surveys analyzed across the four studies. The respondents included workers in direct contact with animals as well as flock owners and veterinarians tending to farms. Handwashing was the most common practice observed among all participants with 42% "always" and 35% "sometimes" washing their hands after contact with the animals. This practice was least common among Minnesota swine workers. Even Thai poultry farmers, who demonstrated the lowest overall PPE use, reported a higher frequency of handwashing. Mask use during animal farming activities ("always" or "sometimes") was least commonly practiced, ranging from 1% in Thailand to 26% among backyard poultry farmers in Minnesota. Minnesota poultry and swine farmers had similar frequencies of mask (26%) and glove use (51% and 49%). All other comparisons differed significantly across the four sites (p-values <0.05). The use of PPE in animal farming differed by study location and is likely related to prevalent norms in the respective regions. Overall, the use of PPE did not appear to be influenced by the particular animal (poultry or swine) being farmed. These findings may prove useful to regulating bodies and farm owners in formulating policy or planning strategies for improving personal hygiene practices in animal farming and preparing for influenza and other potential zoonotic disease outbreaks.

We estimated the degree to which language used in the high profile medical/public health/epidemiology literature implied causality using language linking exposures to outcomes and action recommendations; examined disconnects between language and recommendations; identified the most common linking phrases; and estimated how strongly linking phrases imply causality. We searched and screened for 1,170 articles from 18 high-profile journals (65 per journal) published from 2010-2019. Based on written framing and systematic guidance, three reviewers rated the degree of causality implied in abstracts and full text for exposure/outcome linking language and action recommendations. Reviewers rated the causal implication of exposure/outcome linking language as None (no causal implication) in 13.8%, Weak 34.2%, Moderate 33.2%, and Strong 18.7% of abstracts. The implied causality of action recommendations was higher than the implied causality of linking sentences for 44.5% or commensurate for 40.3% of articles. The most common linking word in abstracts was "associate" (45.7%). Reviewers’ ratings of linking word roots were highly heterogeneous; over half of reviewers rated "association" as having at least some causal implication. This research undercuts the assumption that avoiding "causal" words leads to clarity of interpretation in medical research.