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1.
Nature ; 625(7995): 548-556, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38123685

RESUMO

Considerable scholarly attention has been paid to understanding belief in online misinformation1,2, with a particular focus on social networks. However, the dominant role of search engines in the information environment remains underexplored, even though the use of online search to evaluate the veracity of information is a central component of media literacy interventions3-5. Although conventional wisdom suggests that searching online when evaluating misinformation would reduce belief in it, there is little empirical evidence to evaluate this claim. Here, across five experiments, we present consistent evidence that online search to evaluate the truthfulness of false news articles actually increases the probability of believing them. To shed light on this relationship, we combine survey data with digital trace data collected using a custom browser extension. We find that the search effect is concentrated among individuals for whom search engines return lower-quality information. Our results indicate that those who search online to evaluate misinformation risk falling into data voids, or informational spaces in which there is corroborating evidence from low-quality sources. We also find consistent evidence that searching online to evaluate news increases belief in true news from low-quality sources, but inconsistent evidence that it increases belief in true news from mainstream sources. Our findings highlight the need for media literacy programmes to ground their recommendations in empirically tested strategies and for search engines to invest in solutions to the challenges identified here.


Assuntos
Desinformação , Probabilidade , Ferramenta de Busca , Confiança , Humanos , Redes Sociais Online , Opinião Pública , Ferramenta de Busca/estatística & dados numéricos , Mídias Sociais/estatística & dados numéricos
2.
Nature ; 625(7993): 134-147, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38093007

RESUMO

Scientific evidence regularly guides policy decisions1, with behavioural science increasingly part of this process2. In April 2020, an influential paper3 proposed 19 policy recommendations ('claims') detailing how evidence from behavioural science could contribute to efforts to reduce impacts and end the COVID-19 pandemic. Here we assess 747 pandemic-related research articles that empirically investigated those claims. We report the scale of evidence and whether evidence supports them to indicate applicability for policymaking. Two independent teams, involving 72 reviewers, found evidence for 18 of 19 claims, with both teams finding evidence supporting 16 (89%) of those 18 claims. The strongest evidence supported claims that anticipated culture, polarization and misinformation would be associated with policy effectiveness. Claims suggesting trusted leaders and positive social norms increased adherence to behavioural interventions also had strong empirical support, as did appealing to social consensus or bipartisan agreement. Targeted language in messaging yielded mixed effects and there were no effects for highlighting individual benefits or protecting others. No available evidence existed to assess any distinct differences in effects between using the terms 'physical distancing' and 'social distancing'. Analysis of 463 papers containing data showed generally large samples; 418 involved human participants with a mean of 16,848 (median of 1,699). That statistical power underscored improved suitability of behavioural science research for informing policy decisions. Furthermore, by implementing a standardized approach to evidence selection and synthesis, we amplify broader implications for advancing scientific evidence in policy formulation and prioritization.


Assuntos
Ciências do Comportamento , COVID-19 , Prática Clínica Baseada em Evidências , Política de Saúde , Pandemias , Formulação de Políticas , Humanos , Ciências do Comportamento/métodos , Ciências do Comportamento/tendências , Comunicação , COVID-19/epidemiologia , COVID-19/etnologia , COVID-19/prevenção & controle , Cultura , Prática Clínica Baseada em Evidências/métodos , Liderança , Pandemias/prevenção & controle , Saúde Pública/métodos , Saúde Pública/tendências , Normas Sociais
3.
Nature ; 620(7972): 137-144, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37500978

RESUMO

Many critics raise concerns about the prevalence of 'echo chambers' on social media and their potential role in increasing political polarization. However, the lack of available data and the challenges of conducting large-scale field experiments have made it difficult to assess the scope of the problem1,2. Here we present data from 2020 for the entire population of active adult Facebook users in the USA showing that content from 'like-minded' sources constitutes the majority of what people see on the platform, although political information and news represent only a small fraction of these exposures. To evaluate a potential response to concerns about the effects of echo chambers, we conducted a multi-wave field experiment on Facebook among 23,377 users for whom we reduced exposure to content from like-minded sources during the 2020 US presidential election by about one-third. We found that the intervention increased their exposure to content from cross-cutting sources and decreased exposure to uncivil language, but had no measurable effects on eight preregistered attitudinal measures such as affective polarization, ideological extremity, candidate evaluations and belief in false claims. These precisely estimated results suggest that although exposure to content from like-minded sources on social media is common, reducing its prevalence during the 2020 US presidential election did not correspondingly reduce polarization in beliefs or attitudes.


Assuntos
Atitude , Política , Mídias Sociais , Adulto , Humanos , Emoções , Idioma , Estados Unidos , Desinformação
4.
Proc Natl Acad Sci U S A ; 121(21): e2321584121, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38739793

RESUMO

We study the effect of Facebook and Instagram access on political beliefs, attitudes, and behavior by randomizing a subset of 19,857 Facebook users and 15,585 Instagram users to deactivate their accounts for 6 wk before the 2020 U.S. election. We report four key findings. First, both Facebook and Instagram deactivation reduced an index of political participation (driven mainly by reduced participation online). Second, Facebook deactivation had no significant effect on an index of knowledge, but secondary analyses suggest that it reduced knowledge of general news while possibly also decreasing belief in misinformation circulating online. Third, Facebook deactivation may have reduced self-reported net votes for Trump, though this effect does not meet our preregistered significance threshold. Finally, the effects of both Facebook and Instagram deactivation on affective and issue polarization, perceived legitimacy of the election, candidate favorability, and voter turnout were all precisely estimated and close to zero.


Assuntos
Política , Mídias Sociais , Humanos , Estados Unidos , Atitude , Masculino , Feminino
5.
J Infect Dis ; 2024 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-39179953

RESUMO

BACKGROUND: Viral respiratory illnesses are the most common acute illnesses experienced and generally follow a predicted pattern over time. The SARS-CoV-2 pandemic interrupted that pattern. METHODS: The HIVE (Household Influenza Vaccine Evaluation) study was established in 2010 to follow a cohort of Southeast Michigan households over time. Initially focused on influenza, surveillance was expanded to include other major respiratory pathogens, and, starting in 2015, the population was followed year-round. Symptoms of acute illness were reported, and respiratory specimens were collected and tested to identify viral infections. Based on the known population being followed, virus-specific incidence was calculated. RESULTS: From 2015 to 2022, 1755 participants were followed in HIVE for 7785 person-years with 7833 illnesses documented. Before the pandemic, rhinovirus (RV) and common cold human coronaviruses (HCoVs) were the viruses most frequently identified, and incidence decreased with increasing age. Type A influenza was next but with comparable incidence by age. Parainfluenza and respiratory syncytial viruses were less frequent overall, followed by human metapneumoviruses. Incidence was highest in young children, but infections were frequently documented in all age groups. Seasonality followed patterns established decades ago. The SARS-CoV-2 pandemic disrupted these patterns, except for RV and, to a lesser extent, HCoVs. In the first two years of the pandemic, RV incidence far exceeded that of SARS-CoV-2. CONCLUSION: Longitudinal cohort studies are important in comparing the incidence, seasonality, and characteristics of different respiratory viral infections. Studies documented the differential effect of the pandemic on the incidence of respiratory viruses in addition to SARS-CoV-2.

7.
Proc Natl Acad Sci U S A ; 118(25)2021 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-34131075

RESUMO

Despite the belief that social media is altering intergroup dynamics-bringing people closer or further alienating them from one another-the impact of social media on interethnic attitudes has yet to be rigorously evaluated, especially within areas with tenuous interethnic relations. We report results from a randomized controlled trial in Bosnia and Herzegovina (BiH), exploring the effects of exposure to social media during 1 wk around genocide remembrance in July 2019 on a set of interethnic attitudes of Facebook users. We find evidence that, counter to preregistered expectations, people who deactivated their Facebook profiles report lower regard for ethnic outgroups than those who remained active. Moreover, we present additional evidence suggesting that this effect is likely conditional on the level of ethnic heterogeneity of respondents' residence. We also extend the analysis to include measures of subjective well-being and knowledge of news. Here, we find that Facebook deactivation leads to suggestive improvements in subjective wellbeing and a decrease in knowledge of current events, replicating results from recent research in the United States in a very different context, thus increasing our confidence in the generalizability of these effects.


Assuntos
Etnicidade , Mídias Sociais , Atitude , Genocídio , Saúde , Humanos , Análise de Intenção de Tratamento , Conhecimento , Inquéritos e Questionários
8.
Proc Natl Acad Sci U S A ; 114(28): 7313-7318, 2017 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-28652356

RESUMO

Political debate concerning moralized issues is increasingly common in online social networks. However, moral psychology has yet to incorporate the study of social networks to investigate processes by which some moral ideas spread more rapidly or broadly than others. Here, we show that the expression of moral emotion is key for the spread of moral and political ideas in online social networks, a process we call "moral contagion." Using a large sample of social media communications about three polarizing moral/political issues (n = 563,312), we observed that the presence of moral-emotional words in messages increased their diffusion by a factor of 20% for each additional word. Furthermore, we found that moral contagion was bounded by group membership; moral-emotional language increased diffusion more strongly within liberal and conservative networks, and less between them. Our results highlight the importance of emotion in the social transmission of moral ideas and also demonstrate the utility of social network methods for studying morality. These findings offer insights into how people are exposed to moral and political ideas through social networks, thus expanding models of social influence and group polarization as people become increasingly immersed in social media networks.


Assuntos
Emoções , Princípios Morais , Política , Rede Social , Humanos , Idioma , Política Pública , Mídias Sociais , Estados Unidos
9.
BMC Nurs ; 19(1): 106, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33292208

RESUMO

BACKGROUND: Agitation among patients is a common and distressing behaviour across a variety of health care settings, particularly inpatient mental health. Unless recognised early and effectively managed it can lead to aggression and personal injury. The aim of this paper is to explore the experiences of mental health nurses in recognising and managing agitation in an inpatient mental health setting and the alignment of these experiences with best practice and person-centred care. METHODS: This study used a descriptive qualitative methodology. Semi-structured focus group interviews were conducted with 20 nurses working in a mental health unit in 2018. Nursing staff described their experiences of assessing and managing agitation. Descriptive and Thematic Analysis were undertaken of the transcribed focus group dialogue. RESULTS: Nurses combined their clinical knowledge, assessment protocols and training with information from patients to make an individualised assessment of agitation. Nurses also adopted an individualised approach to management by engaging patients in decisions about their care. In keeping with best practice recommendations, de-escalation strategies were the first choice option for management, though nurses also described using both coercive restraint and medication under certain circumstances. From the perspective of patient-centred care, the care provided aligned with elements of person-centred care nursing care. CONCLUSION: The findings suggest that clinical mental health nurses assess and manage agitation, with certain exceptions, in line with best practice and a person-centred care nursing framework.

10.
Prev Sci ; 18(1): 50-60, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27785662

RESUMO

This meta-analysis examines the effectiveness of interactive middle school-based drug prevention programs on adolescent cannabis use in North America, as well as program characteristics that could moderate these effects. Interactive programs, compared to more didactic, lecture style programs, involve participants in skill-building activities and focus on interaction among participants. A systematic literature search was conducted for English-language studies from January 1998 to March 2014. Studies included evaluations using random assignment or a quasi-experimental design of interactive school-based substance use prevention programs delivered to adolescents (aged 12-14) in North American middle schools (grades 6-8). Data were extracted using a coding protocol. The outcomes of interest were post-treatment cannabis use, intent to use, and refusal skills compared across intervention and control groups. Effect sizes (Cohen's d) were calculated from continuous measures, and dichotomous measures were converted to the d index. A total of 30 studies yielding 23 independent samples were included. The random effects pooled effect size for cannabis use (k = 21) was small ([Formula: see text]= -0.07, p < 0.01) and favorable for the prevention programs. The pooled effect sizes for intention to use (k = 3) and refusal skills (k = 3) were not significant. Moderator analyses indicated significant differences in program effectiveness between instructor types, with teachers found to be most effective ([Formula: see text]= -0.08, p = 0.02). The findings provide further support for the use of interactive school-based programs to prevent cannabis use among middle school students in North America.


Assuntos
Fumar Maconha/prevenção & controle , Serviços de Saúde Escolar , Adolescente , Criança , Feminino , Humanos , Masculino , Avaliação de Programas e Projetos de Saúde , Instituições Acadêmicas
11.
Psychol Sci ; 26(10): 1531-42, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26297377

RESUMO

We estimated ideological preferences of 3.8 million Twitter users and, using a data set of nearly 150 million tweets concerning 12 political and nonpolitical issues, explored whether online communication resembles an "echo chamber" (as a result of selective exposure and ideological segregation) or a "national conversation." We observed that information was exchanged primarily among individuals with similar ideological preferences in the case of political issues (e.g., 2012 presidential election, 2013 government shutdown) but not many other current events (e.g., 2013 Boston Marathon bombing, 2014 Super Bowl). Discussion of the Newtown shootings in 2012 reflected a dynamic process, beginning as a national conversation before transforming into a polarized exchange. With respect to both political and nonpolitical issues, liberals were more likely than conservatives to engage in cross-ideological dissemination; this is an important asymmetry with respect to the structure of communication that is consistent with psychological theory and research bearing on ideological differences in epistemic, existential, and relational motivation. Overall, we conclude that previous work may have overestimated the degree of ideological segregation in social-media usage.


Assuntos
Comunicação , Motivação , Política , Teoria Psicológica , Mídias Sociais/estatística & dados numéricos , Mídias Sociais/tendências , Estados Unidos
12.
Percept Mot Skills ; 120(3): 687-99, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26057420

RESUMO

UNLABELLED: The Åstrand-Ryhming Submaximal Bicycle Test is an accurate and widely used test to estimate maximal oxygen consumption. This test requires a participant to maintain a workload over a 6-min. PERIOD: The issue facing many employing this protocol is the identification of an appropriate workload for the cycling regimen. The present study is designed to identify a method for determining an appropriate workload for female participants. A prior study designed a workload selection procedure specifically for men; however, the selection procedure designed for women in this study was better able to elicit a final heart rate (average of minutes five and six) between 165-170 bpm compared to the original Åstrand-Ryhming procedure.


Assuntos
Ciclismo/fisiologia , Teste de Esforço/métodos , Consumo de Oxigênio/fisiologia , Carga de Trabalho , Adolescente , Adulto , Feminino , Humanos , Adulto Jovem
13.
ACS Appl Mater Interfaces ; 16(19): 25280-25293, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38712718

RESUMO

Composite laminates utilizing autoclave-grade carbon fiber-reinforced plastic (CFRP) prepreg were manufactured using a polymer nanoporous network (NPN) interlayer that generates capillary pressure in lieu of pressure from an autoclave. The polymer nanofiber NPN film is integrated into the interlaminar region and is shown to eliminate voids in a vacuum-bag-only (VBO) curing process. After a preliminary investigation of the effect of NPN thickness on the interlaminar region and performance, an 8 µm thick polymer NPN was selected for a scaled manufacturing demonstration. Combining the polymer NPN with "out-of-oven" (OoO) electrothermal heating of a carbon nanotube (CNT)-heated tool, a 0.6 × 0.6 m void-free plate is successfully manufactured. OoO cure enables an accelerated cure cycle, which reduces the cure time by 35% compared to the manufacturer-recommended cure cycle (MRCC). X-ray microcomputed tomography (µ-CT) reveals that the laminates are void-free and of identical quality to autoclave-cured specimens. An array of mechanical tests including tension, compression, open-hole compression (OHC), tension-bearing (bolt-bearing), and compression after impact, reveal that the accelerated NPN-cured composites were broadly equivalent, with some instances of improved properties, relative to the autoclave-cured parts, e.g., OHC strength increased by 5%. With reduced capital costs, energy consumption, and increased throughput, the facile polymer NPN-enabled out-of-autoclave (OoA) fabrication method is shown to be a practical and attractive alternative to conventional autoclave fabrication.

14.
Nat Commun ; 14(1): 62, 2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36624094

RESUMO

There is widespread concern that foreign actors are using social media to interfere in elections worldwide. Yet data have been unavailable to investigate links between exposure to foreign influence campaigns and political behavior. Using longitudinal survey data from US respondents linked to their Twitter feeds, we quantify the relationship between exposure to the Russian foreign influence campaign and attitudes and voting behavior in the 2016 US election. We demonstrate, first, that exposure to Russian disinformation accounts was heavily concentrated: only 1% of users accounted for 70% of exposures. Second, exposure was concentrated among users who strongly identified as Republicans. Third, exposure to the Russian influence campaign was eclipsed by content from domestic news media and politicians. Finally, we find no evidence of a meaningful relationship between exposure to the Russian foreign influence campaign and changes in attitudes, polarization, or voting behavior. The results have implications for understanding the limits of election interference campaigns on social media.


Assuntos
Mídias Sociais , Humanos , Política , Atitude , Internacionalidade , Federação Russa
15.
Science ; 381(6656): 392-398, 2023 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-37499003

RESUMO

Does Facebook enable ideological segregation in political news consumption? We analyzed exposure to news during the US 2020 election using aggregated data for 208 million US Facebook users. We compared the inventory of all political news that users could have seen in their feeds with the information that they saw (after algorithmic curation) and the information with which they engaged. We show that (i) ideological segregation is high and increases as we shift from potential exposure to actual exposure to engagement; (ii) there is an asymmetry between conservative and liberal audiences, with a substantial corner of the news ecosystem consumed exclusively by conservatives; and (iii) most misinformation, as identified by Meta's Third-Party Fact-Checking Program, exists within this homogeneously conservative corner, which has no equivalent on the liberal side. Sources favored by conservative audiences were more prevalent on Facebook's news ecosystem than those favored by liberals.


Assuntos
Política , Mídias Sociais , Humanos , Comunicação , Ecossistema
16.
Influenza Other Respir Viruses ; 17(3): e13106, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36875204

RESUMO

Background: The annual reappearance of respiratory viruses has been recognized for decades. COVID-19 mitigation measures taken during the pandemic were targeted at respiratory transmission and broadly impacted the burden of acute respiratory illnesses (ARIs). Methods: We used the longitudinal Household Influenza Vaccine Evaluation (HIVE) cohort in southeast Michigan to characterize the circulation of respiratory viruses from March 1, 2020, to June 30, 2021, using RT-PCR of respiratory specimens collected at illness onset. Participants were surveyed twice during the study period, and SARS-CoV-2 antibodies were measured in serum by electrochemiluminescence immunoassay. Incidence rates of ARI reports and virus detections were compared between the study period and a preceding pre-pandemic period of similar duration. Results: Overall, 437 participants reported a total of 772 ARIs; 42.6% had respiratory viruses detected. Rhinoviruses were the most frequent virus, but seasonal coronaviruses, excluding SARS-CoV-2, were also common. Illness reports and percent positivity were lowest from May to August 2020, when mitigation measures were most stringent. Seropositivity for SARS-CoV-2 was 5.3% in summer 2020 and increased to 11.3% in spring 2021. The incidence rate of total reported ARIs for the study period was 50% lower (95% CI: 0.5, 0.6; p < 0.001) than the incidence rate from a pre-pandemic comparison period (March 1, 2016, to June 30, 2017). Conclusions: The burden of ARI in the HIVE cohort during the COVID-19 pandemic fluctuated, with declines occurring concurrently with the widespread use of public health measures. Rhinovirus and seasonal coronaviruses continued to circulate even when influenza and SARS-CoV-2 circulation was low.


Assuntos
COVID-19 , Vacinas contra Influenza , Influenza Humana , Humanos , Pandemias , SARS-CoV-2 , Rhinovirus
17.
Science ; 381(6656): 398-404, 2023 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-37498999

RESUMO

We investigated the effects of Facebook's and Instagram's feed algorithms during the 2020 US election. We assigned a sample of consenting users to reverse-chronologically-ordered feeds instead of the default algorithms. Moving users out of algorithmic feeds substantially decreased the time they spent on the platforms and their activity. The chronological feed also affected exposure to content: The amount of political and untrustworthy content they saw increased on both platforms, the amount of content classified as uncivil or containing slur words they saw decreased on Facebook, and the amount of content from moderate friends and sources with ideologically mixed audiences they saw increased on Facebook. Despite these substantial changes in users' on-platform experience, the chronological feed did not significantly alter levels of issue polarization, affective polarization, political knowledge, or other key attitudes during the 3-month study period.


Assuntos
Mídias Sociais , Humanos , Atitude , Política , Amigos , Algoritmos
18.
Science ; 381(6656): 404-408, 2023 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-37499012

RESUMO

We studied the effects of exposure to reshared content on Facebook during the 2020 US election by assigning a random set of consenting, US-based users to feeds that did not contain any reshares over a 3-month period. We find that removing reshared content substantially decreases the amount of political news, including content from untrustworthy sources, to which users are exposed; decreases overall clicks and reactions; and reduces partisan news clicks. Further, we observe that removing reshared content produces clear decreases in news knowledge within the sample, although there is some uncertainty about how this would generalize to all users. Contrary to expectations, the treatment does not significantly affect political polarization or any measure of individual-level political attitudes.


Assuntos
Política , Mídias Sociais , Humanos , Atitude , Conhecimento , Incerteza
19.
Sci Adv ; 8(39): eabn9418, 2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36179029

RESUMO

We offer comprehensive evidence of preferences for ideological congruity when people engage with politicians, pundits, and news organizations on social media. Using 4 years of data (2016-2019) from a random sample of 1.5 million Twitter users, we examine three behaviors studied separately to date: (i) following of in-group versus out-group elites, (ii) sharing in-group versus out-group information (retweeting), and (iii) commenting on the shared information (quote tweeting). We find that the majority of users (60%) do not follow any political elites. Those who do follow in-group elite accounts at much higher rates than out-group accounts (90 versus 10%), share information from in-group elites 13 times more frequently than from out-group elites, and often add negative comments to the shared out-group information. Conservatives are twice as likely as liberals to share in-group versus out-group content. These patterns are robust, emerge across issues and political elites, and exist regardless of users' ideological extremity.

20.
Sci Adv ; 8(18): eabl3844, 2022 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-35522751

RESUMO

As the primary arena for viral misinformation shifts toward transnational threats, the search continues for scalable countermeasures compatible with principles of transparency and free expression. We conducted a randomized field experiment evaluating the impact of source credibility labels embedded in users' social feeds and search results pages. By combining representative surveys (n = 3337) and digital trace data (n = 968) from a subset of respondents, we provide a rare ecologically valid test of such an intervention on both attitudes and behavior. On average across the sample, we are unable to detect changes in real-world consumption of news from low-quality sources after 3 weeks. We can also rule out small effects on perceived accuracy of popular misinformation spread about the Black Lives Matter movement and coronavirus disease 2019. However, we present suggestive evidence of a substantively meaningful increase in news diet quality among the heaviest consumers of misinformation. We discuss the implications of our findings for scholars and practitioners.

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