Association Test Research Articles

Associations of Implicit and Explicit Sexual Double Standard Endorsement and Sexual Assertiveness with Sexual and Interactional Competence in Emerging Adults.

In this study, among emerging adults, we investigated the interrelationships of explicit and implicit measures of sexual assertiveness (SA) and sexual double standard endorsement (SDS) on the one hand, and different aspects of sexual and interactional competence (SAIC) on the other hand, using Partial Least Squares Path Modeling (PLS-PM) of cross-sectional data. Participants were 159 sexually active, heterosexual individuals in the Netherlands between 18 and 25 years. No exclusion criteria were used. The Sexual Competence and Interaction Competence in Youth and lifetime number of sexual partners were used to measure SAIC. Explicit SA was measured using the Hurlbert Index of Sexual Assertiveness, while Explicit SDS was assessed using the Scale for the Assessment of Sexual Standards in Youth. Two implicit association tests were performed to measure implicit SA and SDS. Participants accessed these computerized reaction time tasks via a secure online data collection platform. Results showed a strong association between the latent factors of sexual attitudes and SAIC. Greater SA and lower SDS were associated with a greater competence level. No gender effects were found.

Association analysis of mitochondrial DNA heteroplasmic variants: Methods and application

We rigorously assessed a comprehensive association testing framework for heteroplasmy, employing both simulated and real-world data. This framework employed a variant allele fraction (VAF) threshold and harnessed multiple gene-based tests for robust identification and association testing of heteroplasmy. Our simulation studies demonstrated that gene-based tests maintained an appropriate type I error rate at α = 0.001. Notably, when 5 % or more heteroplasmic variants within a target region were linked to an outcome, burden-extension tests (including the adaptive burden test, variable threshold burden test, and z-score weighting burden test) outperformed the sequence kernel association test (SKAT) and the original burden test. Applying this framework, we conducted association analyses on whole-blood derived heteroplasmy in 17,507 individuals of African and European ancestries (31 % of African Ancestry, mean age of 62, with 58 % women) with whole genome sequencing data. We performed both cohort- and ancestry-specific association analyses, followed by meta-analysis on both pooled samples and within each ancestry group. Our results suggest that mtDNA-encoded genes/regions are likely to exhibit varying rates in somatic aging, with the notably strong associations observed between heteroplasmy in the RNR1 and RNR2 genes (p < 0.001) and advance aging by the Original Burden test. In contrast, SKAT identified significant associations (p < 0.001) between diabetes and the aggregated effects of heteroplasmy in several protein-coding genes. Further research is warranted to validate these findings. In summary, our proposed statistical framework represents a valuable tool for facilitating association testing of heteroplasmy with disease traits in large human populations.

Oxytocin modulation of explicit pandemic stigma in men with varying social anxiety levels

ObjectiveStigma can create divisions within societies, hindering social cohesion and cooperation. Notably, it has significant public health implications, especially during infectious disease outbreaks like COVID-19. However, little is known about the neural and molecular basis of disease-related stigma and their association with individual differences. MethodsTo address this gap, we performed a double-blind, placebo-controlled, within-subject design study with 70 males, to investigate the effect of intranasal oxytocin (OT) administration on the explicit and implicit processing of disease-related stigma (i.e., COVID-19 stigma). After self-administrated 24 IU of OT or placebo, participants completed a stigma evaluation task and an Implicit Association Test (IAT) to assess the explicit and implicit processes of stigma evaluation, respectively. ResultsThe results showed that oxytocin amplified the differences between participants with high and low social anxiety in explicit COVID-19 stigma, with a higher inclination to attribute the stigmatized status of the stigmatized targets (i.e., COVID-19 related group) to personal causes in high social anxiety individuals, but reduced blame towards the stigmatized targets in low social anxiety individuals under oxytocin compared to placebo treatment. Furthermore, oxytocin strengthened the connections between responsibility attribution and the other processes (i.e., emotional, approach motivation, social deviance). While no modulation of oxytocin on implicit stigma emerged, oxytocin did modulate the associations between specific dimensions of explicit stigma (i.e., social deviance and approach motivation) and implicit stigma. ConclusionIn conclusion, these findings demonstrated that intranasal oxytocin administration could temporally impact the explicit cognitive judgment in disease-related stigma but not the implicit aspect; furthermore, it modulated in distinct ways in individuals with different levels of social anxiety. These findings highlight the trait-dependent oxytocin modulation on disease-related stigma, implying that oxytocin is partly involved in the endocrine system of disease-related stigma. By unraveling the molecular basis of stigma and its association with individual traits, such as social anxiety, we can tailor interventions to meet specific needs of different individuals in the future.

Preservice science teachers’ cognitive structures regarding the cell and its organelles

Learning the cell, one of the basic subjects of science education, by preservice teachers in a comprehensive way is important for making sense of its vital activities and teaching the subject in a meaningful way in the future. The study aimed to determine preservice science teachers' cognitive structures related to the cell and its organelles before and after the Biology course. The study group consists of 32 preservice science teachers. The single-group interrupted time series design was adopted in the study. Data were collected through the word association test. As a result of the data analysis, it was determined that some organelles could not be associated with other organelles, there was no knowledge about the peroxisome organelle before the intervention. It was observed that more comprehensive and interrelated cognitive structures were formed after the intervention and the peroxisome organelle was also added to this structure.

A New Method for Conditional Gene-Based Analysis Effectively Accounts for the Regional Polygenic Background.

Gene-based association analysis is a powerful tool for identifying genes that explain trait variability. An essential step of this analysis is a conditional analysis. It aims to eliminate the influence of SNPs outside the gene, which are in linkage disequilibrium with intragenic SNPs. The popular conditional analysis method, GCTA-COJO, accounts for the influence of several top independently associated SNPs outside the gene, correcting the z statistics for intragenic SNPs. We suggest a new TauCOR method for conditional gene-based analysis using summary statistics. This method accounts the influence of the full regional polygenic background, correcting the genotype correlations between intragenic SNPs. As a result, the distribution of z statistics for intragenic SNPs becomes conditionally independent of distribution for extragenic SNPs. TauCOR is compatible with any gene-based association test. TauCOR was tested on summary statistics simulated under different scenarios and on real summary statistics for a 'gold standard' gene list from the Open Targets Genetics project. TauCOR proved to be effective in all modelling scenarios and on real data. The TauCOR's strategy showed comparable sensitivity and higher specificity and accuracy than GCTA-COJO on both simulated and real data. The method can be successfully used to improve the effectiveness of gene-based association analyses.

Mothers' Knowledge, Attitudes, and Practices Regarding the Prevention and Management of Diarrhea among Children in Pakistan: A Cross-Sectional Study.

Diarrheal disease is the second leading cause of death worldwide in children under 5 years old, after pneumonia. Fortunately, diarrhea is a preventable disease that can be avoided by implementing basic home management strategies. Mothers are essential to its management and prevention; therefore, this study assessed the knowledge, attitudes, and practices of mothers in Pakistan related to diarrheal disease prevention and management. The study was conducted using a cross-sectional design in three cities of Pakistan from September 2022 to December 2022. A questionnaire was used to collect data on mothers' sociodemographic characteristics and their knowledge, attitudes, and practices related to the prevention and management of diarrheal diseases. A total of 356 mothers (81.7% of them were housewives, and 58.4% were 25-34 years old) participated in the study. Data were analyzed using descriptive statistics and tests of association. Significant associations were found between mothers' income, education, and ethnicity and their knowledge, attitudes, and practices regarding the prevention and management of diarrheal diseases (P <0.05). However, no significant association was found between the other variables. The knowledge and attitudes of the mothers regarding the prevention and management of diarrhea were satisfactory; however, their prevention-related practices and home-based management were unsatisfactory. Therefore, community education, formation of health and hygiene committees, and dissemination of user-friendly information are crucial for creating awareness about the prevention and management of diarrheal diseases. These measures can help improve the practices of mothers and reduce the incidence of diarrheal diseases in Pakistan.

Association of non-high-density lipoprotein to high-density lipoprotein ratio (NHHR) with prognosis in cancer survivors: a population-based study in the United States.

Patients with cancer frequently exhibit alterations in serum lipid profiles associated with chemotherapy. It has been reported that lipid distribution in cancer correlates with tumor progression. However, the prognostic value of serum lipid biomarkers in cancer survivors remains a subject of debate. We aim to explore the relationship between non-high-density lipoprotein to high-density lipoprotein ratio (NHHR) and the prognosis of cancer survivors. In this study, we analyzed cancer survivor data from the National Health and Nutrition Examination Survey (NHANES) from 1999-2000 to 2017-2018. The study included prospective cohorts that included total cholesterol (TC) and high-density lipoprotein cholesterol (HDL-C) levels as well as mortality data. Weighted multivariate cox regression models, competing risk models and restricted cubic spline (RCS) models were applied to investigate the association between NHHR and cancer survival. Subgroup and sensitivity analyses were performed to test the robustness of the results. This study involved 4,177 participants, representing about 19.6 million U.S. adults. After adjustment for various factors, the lower NHHR group (≤1.64) had a 31% (HR 1.31; 95% CI [1.11,1.54], p = 0.001) higher risk of death from any cause compared to the higher NHHR group. The link between NHHR and mortality remained stable across most subgroups, with notable interactions for smoking (p = 0.006) and diabetes status (p = 0.046). A J-shaped pattern was observed between NHHR and all-cause mortality, significantly among obesity-related cancer survivors (overall association test p-value = 0.0068, non-linear association test p-value = 0.0016). However, a non-significant negative correlation was observed for cancer-specific mortality (overall association test p-value = 0.48, non-linear association test p-value = 0.66). Considering the competitive risk of heart disease and cancer-specific mortality, there is no difference between the high and low NHHR groups, while the low NHHR group showed an increased risk of non-specific causes of death (p < 0.001). The results of this study suggest that NHHR is an important indicator that is strongly associated with all-cause mortality in cancer survivors, and that this relationship may be influenced by the interaction of diabetes and smoking status. This finding may provide important information for future research and patient management.

Visual complexity, brand gender, and ad effectiveness

Visual complexity is an important factor in the design of advertisements. This research systematically examines the interaction effect between an ad’s visual complexity and brand gender on marketing effectiveness in ad practice. Across a series of seven studies, encompassing an Implicit Association Test (IAT), a Facebook field study, a lab experiment with an incentive-compatible design, and four online experiments, the current research demonstrates that consumers respond more favorably to a masculine (versus feminine) brand when presented with a visually simple (versus complex) ad. This symmetric effect is driven by conceptual fluency (i.e., the ease of deriving meanings). That is, a match between masculine (versus feminine) brands and simple (versus complex) ads makes the ad processing more conceptually fluent, which in turn enhances ad effectiveness. Moreover, a boundary condition for the core effect was identified, such that the effect between an ad’s visual complexity and brand gender is attenuated among consumers with an analytic (versus holistic) thinking style when processing ads. This research advances the literature on visual aesthetics, brand perception, and ad effectiveness. Our findings also offer actionable insights to marketing practitioners regarding the strategies of ad design and brand positioning in the marketplace.

Can a large language model create acceptable dental board-style examination questions? A cross-sectional prospective study

Background/purposeNumerous studies have shown that large language models (LLMs) can score above the passing grade on various board examinations. Therefore, this study aimed to evaluate national dental board-style examination questions created by an LLM versus those created by human experts using item analysis. Materials and methodsThis study was conducted in June 2024 and included senior dental students (n = 30) who participated voluntarily. An LLM, ChatGPT 4o, was used to generate 44 national dental board-style examination questions based on textbook content. Twenty questions for the LLM set were randomly selected after removing false questions. Two experts created another set of 20 questions based on the same content and in the same style as the LLM. Participating students simultaneously answered a total of 40 questions divided into two sets using Google Forms in the classroom. The responses were analyzed to assess difficulty, discrimination index, and distractor efficiency. Statistical comparisons were performed using the Wilcoxon signed rank test or linear-by-linear association test, with a confidence level of 95%. ResultsThe response rate was 100%. The median difficulty indices of the LLM and human set were 55.00% and 50.00%, both within the range of “excellent” range. The median discrimination indices were 0.29 for the LLM set and 0.14 for the human set. Both sets had a median distractor efficiency of 80.00%. The differences in all criteria were not statistically significant (P > 0.050). ConclusionThe LLM can create national board-style examination questions of equivalent quality to those created by human experts.

A retrospective study of the incidence, patterns, and risk factors of retinopathy of prematurity in infants with birth weight &gt;1500 g in a South Indian tertiary care hospital

Abstract: OBJECTIVE: The objective of the study was to determine the incidence, patterns, and risk factors for the development of retinopathy of prematurity (ROP) in infants weighing &gt;1500 g at birth. MATERIALS AND METHODS: A retrospective analysis was done of the ROP screening records between April 2019 and March 2022. All the infants with birth weight &gt;1500 g who underwent ROP screening were included. Data collected included demographic details, details of the risk factors (respiratory distress syndrome [RDS], hypoxia, anemia, septicemia, patent ductus arteriosus, congenital heart disease [CHD], i.e., atrial septal defects or ventricular septal defects, and multiple gestations), and ocular examination findings. Statistical analyses included calculation of mean, range, Chi-square test, and bivariate logistic regression for associations of risk factors with ROP. RESULTS: ROP was noted in 16.6% of the 336 eyes of 168 infants. The mean birth weight and mean gestational age (GA) of the infants were 1850 ± 33 g and 33.33 weeks ± 1.71 weeks, respectively. Eighteen eyes (32.1%) had Stage I, 17 eyes (30.35%) had Stage II, and 11 eyes (19.64%) had Stage III ROP in Zone II. Aggressive ROP was seen in 8 eyes (14.28%) and stage 5 ROP in two eyes (0.59%). Male gender, GA, CHD, and RDS showed a statistically significant association with the development of ROP in these infants. CONCLUSION: ROP was seen in 16.66% of our subjects. Treatment was required in 6.25% of infants. Risk factors for the development of ROP were low gestational age, male gender, the presence of RDS, and congenital heart disease.

Comparing Skin Tones to Shades of Upper Anterior Teeth: An Observational Study among Nigerian Adults.

Skin tones may be predictive of anterior tooth shade. An analysis of the relationship of skin tone to anterior tooth shade within a population may facilitate the prescription of complete dentures with optimal esthetics and realism. This study aimed to assess the relationship between skin tones and shades of upper anterior teeth among a diverse Nigerian adult population. The study was conducted between February and December 2022 among consecutive healthy adults recruited from dental clinics of five teaching hospitals in four cities located across four geopolitical zones of Nigeria. Skin tones were recorded using the National Immigration Service (NIS) Skin Color scale. The Vitapan Classic® shade guide was used to record the tooth shade of the upper central incisors and canines. Bivariate and multivariate tests of associations were performed, and predictive probabilities were developed. A total of 1070 adults with a mean age of 30.8 ± 10 years participated in the study. NIS skin tones 6 (29.8%) and 5 (27.7%) were the most common, while hues A (48.7% in incisors and 48.4 % in canines) and B (41.1% in incisors and 40.1% in canines) were predominant. The values of the incisors and canines were positively related to skin tone (P = 0.001) and age (P = 0.001 for incisors and P = 0.003 for canines). Hue was also significantly associated with skin tone for canines (P = 0.01) and gender (P = 0.001). Regression models showed increasingly darker skin tones were positively related to duller values for incisor teeth (β = 0.173, OR =1.19, P < 0.001). The values for canines were more likely to be >2 (β = 0.118, OR =1.12, P = 0.01), but without significant positive relationship to increasingly darker skin tones (β = -0.99, OR =0.91, P = 0.22). Skin tones were associated with upper anterior tooth shade. There was a positive relationship between skin tones and the shades of upper anterior teeth. Skin tones could guide the clinician in shade selection during complete denture prescriptions.

Correlation of Serum Uric Acid With Cardiovascular Risk in Nigerian Patients.

Studies exploring the relationship between serum uric acid (sUA) and cardiovascular risk in the Nigerian population remain sparse. The study aimed to assess the association between sUA levels and two measures of cardiovascular risk, namely the Framingham 10-year Cardiovascular Risk Score (FRS) and the Atherogenic Index of Plasma (AIP). This retrospective study used data from clinical records of new, previously unregistered patients presenting at a private cardiac hospital over one year from November 2022 to October 2023. In total, 428 patients presented newly to the hospital in that period. The records of 138 patients were included in the project after various exclusions were made including for incomplete anthropometric and laboratory data. Statistical tests of association were used to determine the significance of the relationship between sUA levels and the measures of cardiovascular risk. Two-tailed p <0.05 was deemed statistically significant. Hyperuricemia was more prevalent in individuals with central obesity, i.e., waist circumference ≥94cm in males or 80cm in females (93.4% vs 6.6%; p=0.03). Serum uric acid also positively correlated with FRS (correlation coefficient: 0.190; p<0.05) and serum triglyceride levels and AIP (correlation coefficient: 0.259 and 0.294, respectively; p<0.001 for both). After multivariate analyses, uric acid was significantly and independently associated with high FRS and AIP after adjusting for age, smoking and diabetes history, blood pressure, total and high-density lipoprotein cholesterol, serum triglyceridesand waist circumference (p<0.001). The results emphasize the emergence of sUA as a pertinent cardiovascular risk factor in clinical settings. More research is needed to deduce the relationship, if any, between cardiovascular risk reduction and pharmacological reduction of sUA levels.

Genomic Data Characterize Reproductive Ecology Patterns in Michigan Invasive Red Swamp Crayfish (Procambarus clarkii).

The establishment and spread of invasive species are directly related to intersexual interactions as dispersal and reproductive success are related to distribution, effective population size, and population growth. Accordingly, populations established by r-selected species are particularly difficult to suppress or eradicate. One such species, the red swamp crayfish (Procambarus clarkii) is established globally at considerable ecological and financial costs to natural and human communities. Here, we develop a single nucleotide polymorphism (SNP) loci panel for P. clarkii using restriction-associated DNA-sequencing data. We use the SNP panel to successfully genotype 1800 individuals at 930 SNPs in southeastern Michigan, USA. Genotypic data were used to reconstruct pedigrees, which enabled the characterization of P. clarkii's mating system and statistical tests for associations among environmental, demographic, and phenotypic predictors and adult reproductive success estimates. We identified juvenile cohorts using genotype-based pedigrees, body size, and sampling timing, which elucidated the breeding phenology of multiple introduced populations. We report a high prevalence of multiple paternity in each surveyed waterbody, indicating polyandry in this species. We highlight the use of newly developed rapid genomic assessment tools for monitoring population reproductive responses, effective population sizes, and dispersal during ongoing control efforts.

Clinical effectiveness of genetic testing guidelines in patients with thoracic aortic aneurysms

ObjectiveTo analyze the effectiveness of the current genetic testing guidelines for patients with thoracic aortic aneurysms. MethodsWe evaluated genetic tests for thoracic aortic disease (TAD) from 2012 to 2023 in patients aged 18 and older with a thoracic aorta diameter greater than 4 cm. Mutation rates were compared by American College of Cardiology/American Heart Association testing criteria met by patients: age younger than 60 years, syndromic features of connective tissue diseases (CTDs), family history, or none. Results were classified as pathogenic, variants of uncertain significance (VUS), or negative. Genes tested were analyzed in 2 categories: primary (strongly associated with heritable diseases) or secondary (less strongly associated). ResultsIn total, 1034 patients were included: 42.4% aged younger than 60 years, 19.1% with syndromic features of CTD, 41.8% with family history, and 30.7% meeting no criteria. Overall, 3.97% had pathogenic mutations, and 27.27% had VUS. Mutation rates were greatest in patients with syndromic features of CTD (13.2%), followed by patients aged younger than 60 years (5.48%), with a family history (4.63%), and with no criteria met (2.21%). Primary genes had pathogenic mutation rates of 3.29% and VUS rates of 12.19%. Secondary genes had lower pathogenic rates (0.68%) but greater VUS (17.5%). Mutation rates in primary genes peaked at 22% in patients meeting all criteria, whereas those younger than 60 years without family history or syndromic features of CTD had the lowest rate (0.54%). ConclusionsRefining genetic testing guidelines to incorporate multiple patient criteria could enhance risk stratification and support informed decision-making in genetic testing for TAD. Limiting testing to genes strongly associated with TAD could lower VUS rates.

Relationship Between Waiting Time and Patient Satisfaction at the Surgery Polyclinic of Bekasi District Hospital

Aims : the study aimed to determine the correlation between waiting time and patient satisfaction at the Surgical Polyclinic of the Outpatient Installation at Bekasi District Hospital. Methods : Time spent waiting serves as the independent variable in this cross-sectional study, with patient satisfaction serving as the dependent variable. Forty participants were surveyed using questionnaires as the major source of information in July 2022. Results : The analysis reveals that P =.000 (P Value.05) is derived from a Chi Square test of association between waiting time factors and patient satisfaction. Patient happiness seems to correlate with how long they have to wait before being seen. Strengthen time management skills to ensure that medical care is delivered on time and with the highest possible quality. Conclusions : The research find a significant correlation between patient satisfaction and waiting time in the Surgical Polyclinic at Bekasi District Hospital, suggesting the need for improved time discipline and more responsive medical personnel.

A Study on Non-Suicidal Self-Injury in University Students: The Use of Implicit Association Tests

A Study on Non-Suicidal Self-Injury in University Students: The Use of Implicit Association Tests

Preparedness of Nursing Homes: A Typology and Analysis of Responses to the COVID-19 Crisis in a French Network.

Preparing healthcare systems for emergencies is crucial to maintaining healthcare quality. Nursing homes (NHs) require tailored emergency plans. This article aims to develop a typology of French private NHs and study their early COVID-19 responses and mortality outcomes. We conducted a cross-sectional survey among NHs of a French network consisting of 290 facilities during the first wave of the COVID-19 pandemic. A Hierarchical Clustering on Principal Components (HCPC) was conducted to develop the typology of the NHs. Association tests were used to analyze the relationships between the typology, prevention and control measures, COVID-19 mortality, and the satisfaction of hospitalization requests. The 290 NHs vary in size, services, and location characteristics. The HCPC identified three clusters: large urban NHs with low levels of primary care (Cluster 1), small rural NHs (Cluster 2), and medium urban NHs with high levels of primary care (Cluster 3). The COVID-19 outcomes and response measures differed by cluster, with Clusters 1 and 2 experiencing higher mortality rates. Nearly all the NHs implemented preventive measures, but the timing and extent varied. This typology could help in better preparing NHs for future health emergencies, allowing for targeted resource allocation and tailored adaptations. It underscores the importance of primary care territorial structuring in managing health crises.

Association between optic disc pallor and lacunar stroke

ObjectiveTo test for associations between optic disc pallor and two clinical variables: ischaemic stroke subtype (cortical and lacunar) and cerebral small vessel disease (SVD) scores in a cohort of hospital...

A scalable adaptive quadratic kernel method for interpretable epistasis analysis in complex traits.

Our knowledge of the contribution of genetic interactions (epistasis) to variation in human complex traits remains limited, partly due to the lack of efficient, powerful, and interpretable algorithms to detect interactions. Recently proposed approaches for set-based association tests show promise in improving the power to detect epistasis by examining the aggregated effects of multiple variants. Nevertheless, these methods either do not scale to large Biobank data sets or lack interpretability. We propose QuadKAST, a scalable algorithm focused on testing pairwise interaction effects (quadratic effects) within small to medium-sized sets of genetic variants (window size ≤100) on a trait and provide quantified interpretation of these effects. Comprehensive simulations show that QuadKAST is well-calibrated. Additionally, QuadKAST is highly sensitive in detecting loci with epistatic signals and accurate in its estimation of quadratic effects. We applied QuadKAST to 52 quantitative phenotypes measured in ≈300,000 unrelated white British individuals in the UK Biobank to test for quadratic effects within each of 9515 protein-coding genes. We detect 32 trait-gene pairs across 17 traits and 29 genes that demonstrate statistically significant signals of quadratic effects (accounting for the number of genes and traits tested). Across these trait-gene pairs, the proportion of trait variance explained by quadratic effects is comparable to additive effects, with five pairs having a ratio >1. Our method enables the detailed investigation of epistasis on a large scale, offering new insights into its role and importance.

Recent evolutionary origin and localized diversity hotspots of mammalian coronaviruses

Several coronaviruses infect humans, with three, including the SARS-CoV2, causing diseases. While coronaviruses are especially prone to induce pandemics, we know little about their evolutionary history, host-to-host transmissions, and biogeography. One of the difficulties lies in dating the origination of the family, a particularly challenging task for RNA viruses in general. Previous cophylogenetic tests of virus-host associations, including in the Coronaviridae family, have suggested a virus-host codiversification history stretching many millions of years. Here, we establish a framework for robustly testing scenarios of ancient origination and codiversification versus recent origination and diversification by host switches. Applied to coronaviruses and their mammalian hosts, our results support a scenario of recent origination of coronaviruses in bats and diversification by host switches, with preferential host switches within mammalian orders. Hotspots of coronavirus diversity, concentrated in East Asia and Europe, are consistent with this scenario of relatively recent origination and localized host switches. Spillovers from bats to other species are rare, but have the highest probability to be towards humans than to any other mammal species, implicating humans as the evolutionary intermediate host. The high host-switching rates within orders, as well as between humans, domesticated mammals, and non-flying wild mammals, indicates the potential for rapid additional spreading of coronaviruses across the world. Our results suggest that the evolutionary history of extant mammalian coronaviruses is recent, and that cases of long-term virus–host codiversification have been largely over-estimated.