Conclusions about human behavior are primarily based upon observations from western, educated, industrialized, rich, and democratic (WEIRD) samples, especially from the United States. One consequence may be the promotion of assumptions that research findings from these populations are more generalizable to humankind than findings from non-WEIRD populations. We tested this with an archival study comparing the extent to which titles of over 5,000 published psychology articles specify samples’ racial/ethnic/national/cultural characteristics—a practice that implies constraints to generalizability. We observed that samples from the United States were less frequently specified in titles compared to both other WEIRD and non-WEIRD regions. Yet, samples from the United States (compared to other regions) were more frequently specified in titles if they referred to racial/ethnic/cultural minorities who may be perceived as exceptions to assumed generalizability of the White American population. These findings suggest that one consequence of a USA-centric sampling bias in psychology may be biased assumptions of (White) people from the United States as especially reflective of humankind.

Bacillus Calmette-Guérin (BCG) vaccination may reduce the risk of a range of infectious diseases, and if so, it could protect against coronavirus disease 2019 (COVID-19). Here, we compared countries that mandated BCG vaccination until at least 2000 with countries that did not. To minimize any systematic effects of reporting biases, we analyzed the rate of the day-by-day increase in both confirmed cases (134 countries) and deaths (135 countries) in the first 30-day period of country-wise outbreaks. The 30-day window was adjusted to begin at the country-wise onset of the pandemic. Linear mixed models revealed a significant effect of mandated BCG policies on the growth rate of both cases and deaths after controlling for median age, gross domestic product per capita, population density, population size, net migration rate, and various cultural dimensions (e.g., individualism). Our analysis suggests that mandated BCG vaccination can be effective in the fight against COVID-19.

One sentence summaryThe presence of national policies for universal BCG vaccination is associated with flattened growth curves for confirmed cases of COVID-19 infection and resulting deaths in the first 30-day period of country-wise outbreaks. AbstractPrior work suggests that BCG vaccination reduces the risk of different infectious diseases. BCG vaccination may thus serve as a protective factor against COVID-19. Here, we drew on day-byday reports of both confirmed cases and deaths and analyzed growth curves in countries that mandate BCG policies versus countries that do not. Linear mixed models revealed that the presence of mandated BCG policies was associated with a significant flattening of the exponential increase in both confirmed cases and deaths during the first 30-day period of country-wise outbreaks. This effect held after controlling for median age, gross domestic product per capita, population density, population size, net migration rate, and various cultural dimensions (e.g., individualism and the tightness vs. looseness of social norms). Our analysis suggests that mandated BCG vaccination can be effective in the fight against COVID-19.

The disproportionately high rates of both infections and deaths among racial and ethnic minorities (especially Blacks and Hispanics) in the United States during the COVID‐19 pandemic are consistent with the conclusion that structural inequality can produce lethal consequences. However, the nature of this structural inequality in relation to COVID‐19 is poorly understood. Here, we hypothesized that two structural features, racial residential segregation and income inequality, of metropolitan areas in the United States have contributed to health‐compromising conditions, which, in turn, have increased COVID‐19 fatalities; moreover, that these two features, when combined, may be particularly lethal. To test this hypothesis, we examined the growth rate of confirmed COVID‐19 cases and deaths in an early 30‐day period of the outbreak in the counties located in each of the 100 largest metropolitan areas in the United States. The growth curves for cases and deaths were steeper in counties located in metropolitan areas where Blacks and Hispanics are residentially segregated from Whites. Moreover, the effect of racial residential segregation was augmented by income inequality within each county. These data strongly suggest that racial and economic disparities have caused a greater death toll during the current pandemic. We draw policy implications for making virus‐resilient cities free from such consequences.

During the current COVID-19 pandemic, racial minorities in the United States, particularly Blacks and Hispanics, account for a disproportionate percent of deaths. The unequal distribution of COVID-related fatalities along the racial lines may result from the segregation of Blacks and Hispanics in neighborhoods afflicted with poverty and all accompanying health-compromising conditions (e.g., discrimination, poor hygiene, congested housing, poor chronic health of residents, and limited access to medical services). We thus anticipated that American cities would be especially vulnerable to COVID-19, thereby exhibiting an accelerated rate of growth of the disease, if they had elevated levels of both economic disparity and racial segregation. To test this expectation, we examined the growth rate of both confirmed COVID-19 cases and deaths in the first 30-day period of the outbreak in the counties subsumed under each of the 100 largest metropolitan cities. We observed that the growth curve was particularly steep in counties with high economic disparity that were located in cities that segregated Blacks and Hispanics. The current evidence underscores an urgent need to build a less segregated, more equal, and thus, more virus-resilient society.