Abdominal muscle activity may contribute to cramping pain in primary dysmenorrhea but is resolvable with naproxen. Dysmenorrheic patients without cramp-associated abdominal muscle activity exhibit widespread pain sensitivity (lower pressure pain thresholds) and are more likely to also have a chronic pain diagnosis, suggesting their cramps are linked to changes in central pain processes. This preliminary study suggests new tools to phenotype menstrual pain and supports the hypothesis that multiple distinct mechanisms may contribute to dysmenorrhea.

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Spatiotemporal gait kinematics and their variability are commonly assessed in clinical and laboratory settings to quantify fall risk. Although the Hawthorne effect, or modifications in participant behavior due to knowledge of being observed, has the potential to impact such assessments, it has received minimal attention in the study of gait—particularly gait variability. The purpose of this study was to quantify the Hawthorne effect on variability and central tendency measures of fall-related spatiotemporal gait parameters. Seventeen healthy young adults walked on a treadmill at a self-selected velocity for 2 minutes under covert evaluation (ie, without awareness of being evaluated) and 2 minutes under overt evaluation. The movement was recorded using motion capture technology, from which we calculated mean value and step-to-step variability (using standard deviation and mean absolute deviation) of step length, step width, percent double support, percent stance phase, and stride time. Although central tendencies were unaffected by evaluation type, four-of-five measures of variability were significantly lower during overt evaluation for at least one-of-two metrics. Our results suggest a Hawthorne effect on locomotor control. Researchers should be aware of this phenomenon when designing research studies and interpreting gait assessments.

Background: Social and psychosocial factors are associated with cardiovascular health (CVH) and may underlie race/ethnic differences in CVH. Quantifying the contribution of individual-level social and psychosocial factors to racial and ethnic differences in CVH may guide strategies to reduce disparities. Methods: In the MESA and MASALA cohorts, Kitagawa-Blinder-Oaxaca decomposition quantified the contributions of social and psychosocial factors to differences in mean CVH score (range 0-14, with 14 indicating optimal CVH) in Black, Chinese, Hispanic, or South Asian compared with White participants. Results: Among 7,978 adults (mean age 61 [SE 10] years, 52% female), there were 1,892 Black (mean CVH score 7.96), 804 Chinese (CVH 9.69), 1,496 Hispanic (CVH 8.00), 1,164 South Asian (CVH 9.16), and 2,622 White (CVH 8.91) participants. The factors that statistically contributed the most to explained differences in mean CVH score were income for Black participants (if mean income in Black participants were equivalent to White participants, Black participants’ mean CVH score would be 0.14 points higher, p<0.05); place of birth for Chinese participants (if proportion of US-born and foreign-born individuals among Chinese adults were equivalent to White participants, Chinese participants’ mean CVH score would be 0.22 points lower, p<0.05); and education for Hispanic and South Asian participants (if educational attainment were equivalent to White participants, Hispanic and South Asian participants’ mean CVH score would be 0.55 points higher and 0.37 points lower, respectively, p<0.05 for both). Conclusions: In this multiethnic US cohort, social and psychosocial factors statistically explained racial and ethnic differences in CVH. Socioeconomic and immigration-related factors contributed the largest magnitude to CVH differences between race and ethnic groups.

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