Wednesday, May 26, 2021

Participants’ intention to vote for male candidates increased with age until candidates were about 45 years old and then slightly decreased. In contrast, participants’ intention to vote for female candidates consistently decreased with candidates’ age

How Candidates’ Age and Gender Predict Voter Preference in a Hypothetical Election. Yiqin Alicia Shen, Yuichi Shoda. Psychological Science, May 21, 2021.

Abstract: Are preferences for political candidates influenced by how old they appear to be? Amazon Mechanical Turk workers and undergraduate students were shown photos of 93 state legislators as candidates in hypothetical elections. Other information about the candidates (e.g., party affiliation) was held constant, randomized, or not presented. For very young candidates (< 35 years old), participants favored women over men. However, participants’ intention to vote for male candidates increased with age until candidates were about 45 years old and then slightly decreased. In contrast, participants’ intention to vote for female candidates consistently decreased with candidates’ age. Perceived attractiveness and warmth accounted for some of the gender differences in the effect of candidates’ perceived age.

Keywords: age, gender, voting, preregistered

The alcohol harm paradox: The hoi polloi suffer from higher rates of alcohol-related harm compared with advantaged groups, despite reporting similar or lower levels of consumption on average

Causal mechanisms proposed for the alcohol harm paradox—a systematic review. Jennifer Boyd, Olivia Sexton, Colin Angus, Petra Meier, Robin C. Purshouse, John Holmes. Addiction, May 17 2021.


Background and Aims: The alcohol harm paradox (AHP) posits that disadvantaged groups suffer from higher rates of alcohol-related harm compared with advantaged groups, despite reporting similar or lower levels of consumption on average. The causes of this relationship remain unclear. This study aimed to identify explanations proposed for the AHP. Secondary aims were to review the existing evidence for those explanations and investigate whether authors linked explanations to one another.

Methods: This was a systematic review. We searched MEDLINE (1946–January 2021), EMBASE (1974–January 2021) and PsycINFO (1967–January 2021), supplemented with manual searching of grey literature. Included papers either explored the causes of the AHP or investigated the relationship between alcohol consumption, alcohol-related harm and socio-economic position. Papers were set in Organization for Economic Cooperation and Development high-income countries. Explanations extracted for analysis could be evidenced in the empirical results or suggested by researchers in their narrative. Inductive thematic analysis was applied to group explanations.

Results: Seventy-nine papers met the inclusion criteria and initial coding revealed that these papers contained 41 distinct explanations for the AHP. Following inductive thematic analysis, these explanations were grouped into 16 themes within six broad domains: individual, life-style, contextual, disadvantage, upstream and artefactual. Explanations related to risk behaviours, which fitted within the life-style domain, were the most frequently proposed (n = 51) and analysed (n = 21).

Conclusions: While there are many potential explanations for the alcohol harm paradox, most research focuses on risk behaviours while other explanations lack empirical testing.


This review examined explanations for the AHP to identify potential pathways and mechanisms which result in differential risk of harm between SEP groups. This is a new approach, and goes beyond previous systematic reviews and meta-analyses which have so far established the existence of the AHP and the contribution of alcohol to this relationship [318]. We identified 16 themes within six domains used to explain the AHP. Risk behaviours were the most prevalent explanations. This finding, paired with the dominance of the behavioural paradigm in empirical work, suggests that there has been a reliance upon using risk behaviour to understand the AHP. Evidence found in this review opposed the idea that the AHP was an artefact. There were many other, mainly hypothetical, explanations for the AHP proposed in the literature. This included individual-level mechanisms (e.g. biological or psychological), contextual factors (e.g. place-based factors), the lived experience of disadvantage and upstream structural factors (e.g. the economy and politics). In part, this reflects an awareness that the AHP is complex; there is no simple explanation, and researchers do not view causes in isolation. However, it remains unclear why other re-occurring explanations (e.g. social support or access to health care) have been neglected, while researchers frequently return to risk behaviours. This is particularly puzzling, given that quantitative evidence suggests that risk behaviours only play a partial role [447].

There are two potential reasons for this: theoretical and methodological. Study of the AHP is rooted in alcohol epidemiology, which singularly focuses upon the causes and effects of alcohol consumption [65]. More broadly, the field of epidemiology has faced criticism regarding its approach to understand population health. One of the earliest critiques by Krieger points to fundamental errors in developing epidemiological methods rather than theory, with greater weight given to proximal risk factors and a focus upon causes without context [66]. These limitations have led to an emphasis upon individual disease susceptibility and individual-level interventions. Instead, Krieger argues that the eco-social perspective (the idea that biology and biological changes are shaped by the social environment) should be used to understand health [66]. Concerns regarding how causation is viewed in epidemiology have persisted in contemporary public health, with similar criticisms raised more recently [67]. These concerns continue, despite efforts to raise the profile of theories such as the eco-social perspective and calls to adopt pluralist approaches to causality in epidemiology, which stipulate that causation is not a single connection between two things, but the context in which a causal relationship is observed plays a role [67]. Adopting such an approach would change the way alcohol researchers conceptualize and investigate the AHP.

The lack of clear theoretical structuring in epidemiology, which is argued to have led to a focus upon proximal risk factors (e.g. risk behaviours), could also be a symptom of a lack of methods to carry out more complex analyses of distal factors. Possible solutions to this include the use of complex system modelling methods, which have gained traction within public health and are now being implemented in a UK-based project to gain insight into the causal relationships between policy and health-related outcomes [68]. Software architecture has also recently been devised to address how theory can be systematically incorporated into individual-level and agent-based computer simulations to understand health and health behaviours [69]. Applying these computer simulation methods to the AHP could provide the opportunity to shift the empirical focus from risk behaviours to wider determinants, as they can capture complexity and are mechanism-based rather than focused upon testing relationships between variables.

Strengths and limitations

This is the first review, to our knowledge, to catalogue explanations provided for the AHP across a breadth of literature. In taking a broad approach to literature searching and inclusion criteria it was possible to review work from multiple disciplines employing varied methodologies. This led to the identification of a varied set of explanations. However, it is possible that some explanations are more appropriate, depending upon the study design, population and measure of harm. As the primary aim of this review was to collate and review explanations more generally, we did not conduct an in-depth exploration of this issue. However, upon examination there was no evidence that study design or population influenced which explanations were presented. In terms of measures, we found one clear example of an explanation only applicable when using a subjective measure of alcohol harm—those in low SEP groups who drink may feel their outcomes are worse because their peers are more likely to be abstainers [8]. This issue awaits further examination.

This review was restricted to high-income countries. The results and conclusions are therefore only applicable to this context. Furthermore, most papers focused upon the United Kingdom, which may limit generalizability. This was justified, given substantial differences in alcohol environments. However, given that alcohol is a global issue [1], future research should gain insight into how alcohol affects the disadvantaged in low–middle-income countries to help address the deepening of local and global health inequalities.

Another limitation is that only one reviewer screened and extracted data from the papers. We recruited an independent researcher to re-assess a sample of papers for inclusion and extraction. Cross-checking between the two reviewers demonstrated good reliability.

Research and policy implications

The lack of explicit theory used to present explanations is a barrier to understanding the causes of the AHP. The development or application of theory may be fundamental to identify the true causal mechanisms which create and sustain the AHP. Several explanations have been proposed which align with the vast literature detailing theories of health inequality more generally. The eco-social perspective, among those more commonly discussed [e.g. the materialist (the link between wealth and resources and health) or political economy perspective (the idea that risk factors for health inequalities are rooted in structures)] [70], are just some examples of health inequality theory which could be applied to understand the AHP.

The AHP is well-evidenced, and behavioural-related explanations play a partial role. However, these explanations fall short in understanding the complex causes of inequalities in alcohol-related harm. There is a current lack of evidence investigating other explanations found in this review, which makes it difficult to suggest potential interventions to mitigate the AHP. Future research should empirically investigate these alternative explanations for the AHP. Computer simulations models offer one potential way of achieving this aim in the short term and for relatively low cost.

Based on the evidence from this review, the key policy implication is that tackling drinking alone will not reduce inequalities in alcohol-related harm. While there is some evidence that improving multiple health behaviours may attenuate the risk of alcohol-related harm, it is critical that policymakers look to policies outside the scope of public health to mitigate the inequality produced by the paradox.

San Francisco’s flavor ban was associated with more than doubled odds of recent smoking among underage high school students relative to concurrent changes in other districts

A Difference-in-Differences Analysis of Youth Smoking and a Ban on Sales of Flavored Tobacco Products in San Francisco, California Abigail S. Friedman. JAMA Pediatr., May 24, 2021.

Restrictions on flavored tobacco product sales are increasingly popular; 5 US states and hundreds of localities have implemented them in the past few years alone. Yet only 1 study,1 to my knowledge, has considered how complete flavor bans applying to electronic nicotine delivery systems and combustible tobacco products, without retailer exemptions, are associated with tobacco use. A convenience sample of residents of San Francisco, California, aged 18 to 34 years who had ever used a tobacco product showed significant reductions in any tobacco use following the city’s flavor ban, with a marginally significant increase in combustible cigarette use (smoking) among those aged 18 to 24 years.1 Absent a comparison group, however, it is impossible to ascertain if preexisting trends could have driven these findings.

Given the relative health costs of smoking vs vaping nicotine,2,3 flavor bans that increase smoking may prove harmful. Thus, this study’s objective was to estimate the association between San Francisco’s ban on flavored tobacco product sales and smoking among high school students younger than 18 years.


Data came from the 2011-2019 Youth Risk Behavior Surveillance System (YRBSS) biennial school district surveys, with consideration restricted to districts with representative smoking data (with response rates ≥60%) available through the US Centers for Disease Control and Prevention for each wave: New York City, New York; Broward County, Florida; Los Angeles, California; Orange County, Florida; Palm Beach County, Florida; Philadelphia, Pennsylvania; and San Diego, California, as well as San Francisco, California. This analysis focused on high school students younger than 18 years who had nonmissing data for the outcome of interest: a binary indicator for recent (ie, past 30-day) smoking. This study was deemed exempt from institutional review board review under US federal regulation 45 CFR 46.101(b)(4). The analysis used publicly available YBRSS data, a survey with collection procedures designed to maintain student anonymity; therefore, informed consent was not required.


Recent vaping was not considered because of likely confounding. California legalized recreational marijuana use the same year San Francisco’s flavor ban went into effect; in addition, the YRBSS’s vaping questions did not distinguish vaping nicotine vs marijuana.

Covariates captured age, sex, and race/ethnicity fixed effects and tobacco policies on January 1 of the survey year (specifically, state-plus-district conventional cigarette taxes and indicators for smoke-free restaurant laws). San Francisco did not implement other new tobacco control policies between the 2017 and 2019 surveys.4



[...] Difference-in-differences analyses found that San Francisco’s flavor ban was associated with more than doubled odds of recent smoking among underage high school students relative to concurrent changes in other districts (adjusted odds ratio, 2.24 [95% CI, 1.42-3.53]; P = .001; Figure 2). This result was robust to adjustment for district-specific time trends (adjusted odds ratio, 2.32 [95% CI, 1.45-3.70]; P < .001) and limiting consideration to California (adjusted odds ratio, 2.01 [95% CI, 1.15-3.51]; P = .01).


San Francisco’s ban on flavored tobacco product sales was associated with increased smoking among minor high school students relative to other school districts. While the policy applied to all tobacco products, its outcome was likely greater for youths who vaped than those who smoked due to higher rates of flavored tobacco use among those who vaped.5 This raises concerns that reducing access to flavored electronic nicotine delivery systems may motivate youths who would otherwise vape to substitute smoking. Indeed, analyses of how minimum legal sales ages for electronic nicotine delivery systems are associated with youth smoking also suggest such substitution.6

This study’s primary limitation is generalizability. Future research should assess whether estimates hold over time and in other localities and consider how policy heterogeneity (eg, retailer exemptions) modifies such bans’ outcomes.

Despite substantial changes in group composition, chimpanzees adhered for 12 years to arbitrary group-specific greetings not explained by genetics or the environment; seems that our conventions are rooted in our evolutionary history

Temporal stability of chimpanzee social culture. Edwin J. C. van Leeuwen. Royal Society Biology Letters, May 26 2021.

Abstract: Culture is a hallmark of the human species, both in terms of the transmission of material inventions (e.g. tool manufacturing) and the adherence to social conventions (e.g. greeting mannerisms). While material culture has been reported across the animal kingdom, indications of social culture in animals are limited. Moreover, there is a paucity of evidencing cultural stability in animals. Here, based on a large dataset spanning 12 years, I show that chimpanzees adhere to arbitrary group-specific handclasp preferences that cannot be explained by genetics or the ecological environment. Despite substantial changes in group compositions across the study period, and all chimpanzees having several behavioural variants in their repertoires, chimpanzees showed and maintained the within-group homogeneity and between-group heterogeneity that are so characteristic of the cultural phenomenon in the human species. These findings indicate that human culture, including its arbitrary social conventions and long-term stability, is rooted in our evolutionary history.

4. Discussion

For a behaviour to be labelled ‘cultural’, scholars typically evaluate the behaviour for its (i) emergence through social learning, (ii) sharedness among group members (and absence or difference for members of other groups) and (iii) longevity [14,39,40]. While a plethora of studies have documented socially learned behavioural traditions in animals [41,42], to my knowledge, there is a paucity with respect to evidencing the stability of traditions.

One established example of cultural persistence in animals concerns tool use in wild chimpanzees: over a period of 25 years, group differences with respect to tool-material selection for nut cracking remained highly similar, despite a large number of (female) migrations [43,44]. Material culture has plausibly been part of chimpanzees' repertoire for thousands of years [45], yet social culture remains to be systematically documented in animals. Recently, cultural transmission of social customs has been suggested for traditions in great apes ([9,10,46]; also see [14,47]). Moreover, social culture in terms of socially learned patterns of association and interaction that result in group-specific sociality has been implied as an explanatory mechanism for non-random social dynamics in animals (e.g. [4854]). In these studies, some forms of stability were documented—for instance, neighbouring groups of meerkats (Suricata suricatta) differed consistently in the time of day on which they emerged from their burrows across a decade [54], and reef sharks (Carcharhinus amblyrhynchos) were found to gather in the same close association cliques annually across four consecutive years, presumably to benefit from public information regarding food patches [52]. Arguably the best-documented case of social culture in animals comes from observations on troops of wild olive baboons (Papio anubis) living in the Masai Mara Reserve of Kenya. Owing to the simultaneous deaths of a substantial number of aggressive adult males (caused by a selective outbreak of tuberculosis), the respective ‘Forest Troop’ became a group of relatively socially tolerant and non-aggressive members in comparison to another group living in the same reserve (Talek troop) and the Forest Troop pre-dating the deaths [48,53]. Despite a substantial influx of new group members, across a period of at least 10 years, the Forest Troop remained markedly characterized by what the authors called a culture of ‘pacifism’—relatively high rates of grooming and affiliation, relaxed dominance hierarchies and an overall tendency of non-aggressive interactions, even between resident females and newly immigrated males [48].

Here, I report the multiyear (12 years) stability of a variational cultural practice [24], which is plausibly devoid of any ecological relevance. Whereas material cultures [7,55], but also culturally induced social foraging [52] and dyadic interactions [48,53] are behaviours with clear adaptive value [56], the precise variant by which chimpanzees engage in the handclasp grooming does not bear any relevance to survival or fitness. As such, stability in variant preference might be even less expected given the lack of eliciting affordances in the environment (e.g. the presence of termites might (re-)trigger termite fishing). In analogy to human culture: whereas the motivation for bridging social distances gives rise to greeting behaviours universally, the exact manner in which the greeting gesture emerges (and perpetuates) is highly culture specific [57,58]. The here reported group differences are also difficult to explain based on genetics: the study groups do not systematically differ in their subspecies composition, and whereas the handclasp behaviour an sich could be hypothesized to be under positive genetic selection [59] (i.e. its function is still largely unknown), the relative style preferences by which the groups choose to handclasp seem harder to place in such a selectionist framework (also see [11,24]). The finding that female dyads engaged more in palm clasping while male dyads engaged more in wrist clasping could be due to the fact that chimpanzee males may use the handclasp as a means to confirm or assert dominance over the partner. The subject's wrist position allows the partner to support the weight of the subject's clasping arm, which can be viewed as a prosocial act by the partner [11]. Albeit plausible, more research is needed to investigate this conjecture, including how such configurations are initiated.

Between-group heterogeneity is expected to gradually transition toward homogeneity owing to factors like drift, the natural cycle of births and deaths, and migrations, unless there are mechanisms in place to prevent this, like in humans [2]. Despite such changes of group composition in the studied chimpanzees, the group-specific variant preferences remained, suggesting the workings of stability-fostering mechanisms (also see [43,60]). One potent mechanism promoting group-level cultural stability is conformity—the tendency to copy the behaviour of the majority [2,28]. Whether chimpanzees are conformists remains disputed [43,6164]—yet, the findings of this study warrant scrutiny of any chimpanzee behaviour that could bolster within-group cultural homogeneity across extended periods of time. In any case, where the minimal genetic and environmental variation across groups allows for inferring the cultural nature of the handclasp styles by means of the method of exclusion (also see [24,25]), the observed temporal stability of group-specific style preferences despite substantial population turnover provides a positive indication of the cultural hypothesis.

Recapitulating, chimpanzees retained group-specific grooming style preferences across a 12-year study period in which a substantial number of individuals replaced original group members owing to births, deaths and translocations. This stability of cultural variants indicates that (i) preliminary findings on social culture in chimpanzees are robust, (ii) animals can develop and maintain cultural preferences in the domain of arbitrary, non-fitness-related phenomena, much like the human species and (iii) animal cultures can possess the necessary ingredients in terms of variant adherence and longevity to be a potent force in gene–culture coevolutionary dynamics, thus shaping both phenotypes and genotypes in animals [12,13].

Extraversion development & sport participation effects: Children and adolescents who dropped out of sport showed greater decreases in extraversion than those who continued participation in sport

Extraversion development in childhood, adolescence and adulthood: Testing the role of sport participation in three nationally-representative samples. Mark S. Allen et al. Journal of Sports Sciences, May 20 2021.

Abstract: This research sought to test whether sport participation relates to the development of trait extraversion across three life phases. Sport participation and extraversion were measured in children aged 10.5 ± 0.5 years (n = 3600), in adolescents aged 14.5 ± 0.5 years (n = 3463), and in adults with a mean age of 49.4 ± 18.0 years (n = 12,280), with corresponding data collected four years earlier. There were small mean-level decreases in extraversion during childhood and adulthood, and a large decrease in extraversion during adolescence. Four-year rank-order stability in extraversion was .58 in childhood, .61 in adolescence and .76 in adulthood. Sport participation was associated with higher extraversion in all three samples. After controlling for sociodemographic factors, children and adolescents who dropped out of sport showed greater decreases in extraversion than those who continued participation in sport. Sport participation was unrelated to mean-level change in extraversion during adulthood. Sport participation was also associated with greater intra-individual stability in extraversion for children, adolescents and adults. There were no significant sex moderation effects for mean-level change or individual-level stability. These findings provide evidence that sport participation might have an important role in trait extraversion stability and change across the lifespan.

KEYWORDS: Child developmentintroversionlongitudinalpersonalityyouth sport

Neuroanatomy of Transgender Identity: Transgender persons differed significantly from cisgender persons with respect to (sub)cortical brain volumes and surface area, but not cortical thickness

Mueller SC, Guillamon A, Zubiaurre-Elorza L, et al. The Neuroanatomy of Transgender Identity: Mega-Analytic Findings From the ENIGMA Transgender Persons Working Group. J Sex Med 2021;XXX:XXX–XXX. May 21 2021.


Background: In contrast to cisgender persons, transgender persons identify with a different gender than the one assigned at birth. Although research on the underlying neurobiology of transgender persons has been accumulating over the years, neuroimaging studies in this relatively rare population are often based on very small samples resulting in discrepant findings.

Aim: To examine the neurobiology of transgender persons in a large sample.

Methods: Using a mega-analytic approach, structural MRI data of 803 non-hormonally treated transgender men (TM, n = 214, female assigned at birth with male gender identity), transgender women (TW, n = 172, male assigned at birth with female gender identity), cisgender men (CM, n = 221, male assigned at birth with male gender identity) and cisgender women (CW, n = 196, female assigned at birth with female gender identity) were analyzed.

Outcomes: Structural brain measures, including grey matter volume, cortical surface area, and cortical thickness.

Results: Transgender persons differed significantly from cisgender persons with respect to (sub)cortical brain volumes and surface area, but not cortical thickness. Contrasting the 4 groups (TM, TW, CM, and CW), we observed a variety of patterns that not only depended on the direction of gender identity (towards male or towards female) but also on the brain measure as well as the brain region examined.

Clinical Translation: The outcomes of this large-scale study may provide a normative framework that may become useful in clinical studies.

Strengths and Limitations: While this is the largest study of MRI data in transgender persons to date, the analyses conducted were governed (and restricted) by the type of data collected across all participating sites.

Conclusion: Rather than being merely shifted towards either end of the male-female spectrum, transgender persons seem to present with their own unique brain phenotype.