Factor 06 of 9
Social factors
Relationships and group dynamics: isolation, conformity, in-group bias, harmful ties, and missing mentors.
Barriers within this factor
Each barrier has its own page with the evidence and sources behind it.
- 1Isolation and loneliness
Holt-Lunstad, Smith, and Layton (2010) found strong social relationships were associated with about a 50% higher likelihood of survival. Putnam (2000) documented declines in U.S. community participation.
Evidence and sources (3 evidence points, 4 experimental methods)
- 2Conformity and groupthink
Asch (1956) showed many people agree with a group's clearly wrong answer. Janis (1972) described how cohesive groups suppress dissent. Janis's model rests mainly on historical case studies and has limited experimental support (rated C).
Evidence and sources (3 evidence points, 4 experimental methods)
- 3In-group bias
Social identity theory (Tajfel and Turner, 1979) explains favoritism toward one's own group and suspicion of outsiders.
Evidence and sources (2 evidence points, 5 experimental methods)
- 4Harmful relationships
Harmful relationships, such as abuse, neglect, or control, undermine autonomy and self-worth. Childhood abuse and household dysfunction are covered under early-life adversity in the biological factor.
Evidence and sources (3 evidence points, 6 experimental methods)
- 5Lack of mentors and networks
A lack of mentors and networks cuts people off from information and introductions.
Evidence and sources (3 evidence points, 5 experimental methods)
- 6Status anxiety and social comparison
Status anxiety and social comparison are intensified by social media. When incomes at the top of the U.S. distribution rose, non-rich households spent more on visible goods and saved less (Bertrand and Morse, 2016).
Evidence and sources (3 evidence points, 3 experimental methods)
Evidence strength
Main findings behind this page, grouped by the strength ratings, from strongest to weakest. Each tier lists the findings that received that rating.
| Strength | Findings |
|---|---|
| Strong | The Asch conformity effect in the laboratory. |
| Moderate | Survival benefit of strong social ties (observational). In-group favoritism. Partner violence prevalence (modeled). Trickle-down consumption (debated). |
| Limited | Groupthink. The benefits of mentoring (advocacy organization data). Partner violence and employment. |
| Contested or debated | The effect of neighbors' earnings on happiness. |
Actions that can reduce these barriers
Proven actions for the social barriers have not yet been researched. Each barrier below lists proposed and experimental methods only, with the stage labels and ratings explained below.
Proposed and experimental methods
Each barrier also has a list of proposed and experimental methods. It covers methods that are proposed, under trial, approved in some places but not widely used, or tried and then failed or reversed, so readers can see what is being tested. Each method has a stage label and an evidence rating in parentheses. The stage labels are Theoretical (proposed but not yet tested as an intervention), Early trial (small or first studies), Large trial (large randomized or field trials), Approved but not scaled (legally approved or running in some places but not widely adopted), In wide use (widely adopted but newly tested or questioned), Sold commercially without trials (used for polygenic embryo screening), and Failed or reversed (tested and shown not to work, or adopted and then withdrawn). The word contested is added where the evidence is disputed. Failed, reversed, and unhelpful methods are listed last and begin with "Failed," "Reversed," or "Not shown to help." A stage label shows how far a method has progressed, not whether it works, and the rating shows the strength of the evidence.
Ideal conditions that counter this factor
Exposure, mentorship, and door-openers
What the evidence shows
Childhood exposure to innovation has significant causal effects, and the effects were gender-specific: girls were more likely to invent in fields where more women invented locally (Bell et al., 2019). Pioneers often reached their field through one chance contact. Hardy read a clerk's letter, Davy answered a bookbinder, and Faraday's path began at a public lecture. Bell et al. (2019) estimate that if girls were exposed to female inventors as often as boys are to male inventors, the gender gap in innovation would fall by half, though their analysis does not identify which programs work best. Franklin built a library, an academy, and a learned society for others and declined patents, though patents also reward invention, so the site does not judge which approach produces more progress overall.
Ideal:
- Regular meetings with working scientists, engineers, and inventors, especially people who share the child's background, with exposure programs aimed at children from underrepresented groups who excel early in math and science
- Mentorship that reaches beyond elite schools and families
- Open channels for outsiders, such as review of unsolicited work
- Public lectures and outreach
- Pathways that pioneers build for others
Evidence strength: Mixed. Moderate to strong for exposure effects (rated B), while the mentorship pattern is consistent but anecdotal and the value of institutions built by pioneers rests on historical cases only.
Social conditions and collaboration
What the evidence shows
Wuchty, Jones, and Uzzi (2007) analyzed 19.9 million papers and 2.1 million patents. Teams increasingly dominate nearly all fields and now produce the exceptionally high-impact work once done by solo authors. Franklin's Junto and Einstein's Olympia Academy were small communities of this kind.
Ideal:
- Communities for free cross-field discussion
- Easy ways to find complementary collaborators
- Spaces that allow chance encounters
- Fair credit-sharing norms
Evidence strength: Mixed. Strong for the rise of teams (descriptive, rated A, from a near-complete census of papers and patents). Historical cases only for discussion communities such as the Junto.
In the pioneer cases
Statements from the pioneer records that this site classifies under the social factor. The classification is this site's.
| Pioneer | Effect | Statement |
|---|---|---|
| Albert Einstein | Helped | Max Talmey lent him Aaron Bernstein's popular science books and a geometry textbook. |
| Albert Einstein | Helped | Marcel Grossmann shared lecture notes, his father recommended Einstein for the patent office job, and in 1912 he pointed Einstein to Riemannian geometry for general relativity. Einstein later downplayed Grossmann's role, but historians generally view it as significant. |
| Albert Einstein | Helped | The Olympia Academy. Einstein, Maurice Solovine, and Conrad Habicht met to discuss philosophy and spent weeks on Hume's critique of substance and causality. |
| Albert Einstein | Helped | Michele Besso was the only person thanked in the 1905 relativity paper. |
| Albert Einstein | Note | A close call. He nearly left physics for high-school teaching. One recommendation from Grossmann's father changed his path. |
| Albert Einstein | Note | Mileva Marić. A 1901 letter mentions "our work on relative motion," but most historians reject the claim that she was an unacknowledged coauthor. She was an intellectual companion during his formative years. |
| Albert Einstein | Helped | Max Planck, co-editor of Annalen der Physik, accepted Einstein's light quanta paper despite disliking the idea and was the first scientist to report favorably on relativity. |
| Michael Faraday | Helped | A lucky connection. In 1812 a customer, William Dance, gave him tickets to four Humphry Davy lectures at the Royal Institution. |
| Michael Faraday | Helped | Timing. Davy fired his assistant for fighting and hired Faraday in 1813. |
| Marie Curie | Helped | A family pact. She worked as a governess to fund her sister Bronisława's medical studies in Paris, and Bronisława then helped her. |
| Marie Curie | Helped | A father who taught mathematics and physics. |
| Marie Curie | Helped | An advocate. The 1903 nomination named only Pierre Curie and Becquerel. Gösta Mittag-Leffler alerted Pierre, who insisted Marie share the prize. |
| Srinivasa Ramanujan | Barrier | Poverty, no contact with active mathematicians, and no degree. |
| Srinivasa Ramanujan | Helped | Local supporters, including Madras Port Trust chairman Francis Spring and mathematician Ramachandra Rao, who helped him get a clerkship. |
| Srinivasa Ramanujan | Helped | A sponsor. Hardy's approval raised his status at once. Madras made him a research scholar and Hardy brought him to Cambridge. |
| Jonas Salk | Helped | A mentor. Thomas Francis Jr. trained him on inactivated influenza vaccines. When other positions turned him down, Salk returned to Francis. |
| Jonas Salk | Helped | Mass participation. Volunteers ran the 1954 trial of 1.8 million children. In April 1955 the vaccine was reported safe and 80 to 90% effective against paralytic polio. |
| Jonas Salk | Note | Some colleagues criticized Salk for not crediting the researchers his work built on. |
| Norman Borlaug | Helped | Interdisciplinary teamwork across genetics, breeding, agronomy, soil science, plant pathology, and entomology. |
| Norman Borlaug | Helped | Others' work. He crossed Norin 10, a Japanese dwarf wheat from Orville Vogel, with his rust-resistant varieties. |
| Katalin Karikó | Barrier | In 1995 Penn gave her a choice between abandoning her research and accepting a demotion with a pay cut, as she was diagnosed with cancer and her husband was stuck in Hungary. She described being demoted four times. |
| Katalin Karikó | Helped | A chance meeting. She met Weissman at a photocopier in 1997. |
| Tu Youyou | Barrier | To focus on the work, she left her younger daughter with her parents. By her own account, the child did not recognize her three years later. |
| Tu Youyou | Helped | Collaboration. Other institutes helped determine artemisinin's chemical structure using X-ray crystallography. |
| Tu Youyou | Helped | Outside advocates. In 2011, U.S. National Institutes of Health researchers Louis Miller and Xinzhuan Su reviewed previously confidential documents and concluded that the major credit belonged to Tu. She received the Lasker Award that year. |
| Tu Youyou | Not overcome | Credit remains disputed. Project 523 involved many scientists, and some Chinese scientists and historians object to crediting one person. Tu herself described the discovery as the effort of an entire team. |
| Percy Julian | Barrier | When his family moved to the white suburb of Oak Park, Illinois, around 1950, their home was attacked, including a firebombing. The family stayed. |
| Percy Julian | Helped | A mentor. DePauw chemistry professor William Blanchard encouraged him toward research and later brought him back to DePauw as a research fellow. |
| Percy Julian | Helped | A collaborator. Josef Pikl, a fellow student from Vienna, joined him at DePauw. Together they completed the physostigmine synthesis. |
| Ignaz Semmelweis | Barrier | No support from the top. His chief, Johann Klein, opposed the idea and refused to renew his contract in March 1849. Political differences added to the conflict: Semmelweis's Hungarian patriotism offended Klein, a firm monarchist. |
| Ignaz Semmelweis | Barrier | Delayed publication. He did not publish for years. A supportive colleague, Ferdinand von Hebra, published an editorial about the discovery in 1847, but Semmelweis's own book appeared only in 1861. |
| Ignaz Semmelweis | Barrier | His response alienated allies. When his book was ignored or rejected, he wrote scathing open letters that alienated even his friends. |
| Ignaz Semmelweis | Helped | Colleagues. Josef Škoda and Ferdinand von Hebra supported him, though his chief did not. |
| Ignaz Semmelweis | Not overcome | He left Vienna in 1850. In 1865 he was committed to an asylum, where he died two weeks later of an infection, probably from injuries inflicted by guards. Some historians suggest he may have had a form of dementia. His ideas were vindicated only after his death, as germ theory developed. |
| Mary Wollstonecraft | Barrier | Her family's fortunes were unstable. Her eldest brother, Edward, inherited directly from their grandfather and was the only child to receive a formal education. He became a lawyer, while she received little formal education. This inequality shaped her lifelong views on educating men and women. |
| Mary Wollstonecraft | Helped | A publisher. Joseph Johnson paid an advance on her first book, Thoughts on the Education of Daughters, which eased her debts. He later gave her steady literary work, including reviewing for his Analytical Review from 1788. |
| Mary Wollstonecraft | Helped | A network. Through the Dissenting community led by Richard Price at Newington Green, she met the schoolmaster John Hewlett, who urged her to write for money and obtained ten guineas from Johnson for her first book (Godwin, 1798, chapter 4). |
| Mary Wollstonecraft | Not overcome | She died on 10 September 1797, eleven days after giving birth, of septicemia or puerperal fever. This is the disease that Semmelweis showed, fifty years later, was spread on unwashed hands. Her husband's candid memoir (1798) then damaged her reputation for most of the next century. |
| Baruch Spinoza | Barrier | On July 27, 1656, Amsterdam's Sephardic community issued him the harshest writ of excommunication it ever pronounced. It was never rescinded, and its exact reasons are not known for certain. |
| Baruch Spinoza | Helped | Friends. After his death, friends published his unpublished writings, including the Ethics. |
| Phillis Wheatley | Barrier | She was taken from West Africa and arrived in Boston on the slave ship Phillis in 1761, aged about seven. Her real name is unknown. |
| Phillis Wheatley | Helped | Education at home. The Wheatley family taught her to read and write. |
| Phillis Wheatley | Helped | A patron. Selina Hastings, Countess of Huntingdon, helped pay for the book's publication. |
| Ludwig van Beethoven | Helped | Patronage. In 1809, after he was offered a post as music director to Napoleon's brother in Kassel, Archduke Rudolph and Princes Kinsky and Lobkowitz agreed to pay him 4,000 florins a year. The only condition was that he decline the Kassel offer and stay in Vienna. His friend Ignaz von Gleichenstein led the negotiations. |
| Benjamin Franklin | Barrier | A harsh apprenticeship. At 12 he signed indentures binding him to his brother James, a printer, until age 21. James often beat him, and Franklin eventually ran away to Philadelphia. |
| Benjamin Franklin | Barrier | A broken promise. Pennsylvania's governor, William Keith, encouraged him to go to London to buy printing equipment, but the promised support never came. Franklin worked in London printing houses for about eighteen months before returning. |
| Benjamin Franklin | Helped | A network of peers. He formed the Junto, a discussion club of tradesmen of moderate means seeking self-improvement. |
| Benjamin Franklin | Helped | A door-opener in London. Peter Collinson, a Fellow of the Royal Society, gave the Library Company a glass tube for electrical experiments. Franklin reported his results in letters to Collinson, who arranged their publication in London in 1751 as Experiments and Observations on Electricity. |
| Benjamin Franklin | Helped | Recognition. The Royal Society at first judged his letters not worth printing in its Transactions. After a French experimenter confirmed in May 1752 that lightning is electrical, the Society awarded him the Copley Medal in 1753, its highest scientific honor, and Harvard and Yale gave him honorary degrees the same year. |
| Benjamin Franklin | Note | A library. In 1731 he persuaded Junto members to pool their money for books none could afford alone, founding the Library Company of Philadelphia, the first subscription library in America. |
| Benjamin Franklin | Note | A fire company. In 1736 he organized the Union Fire Company, Philadelphia's first fire protection society. |
| Benjamin Franklin | Note | A learned society. In 1743 he founded the American Philosophical Society. |
| Gregor Mendel | Barrier | He presented his results in two lectures in 1865, and his 1866 paper appeared in the proceedings of a local society. It was largely overlooked for 34 years. |
| Gregor Mendel | Helped | Land, time, and a local society. The monastery gave him garden space for his experiments, and the Natural Science Society of Brno printed his paper. |
| Gregor Mendel | Helped | Later scientists who reached the same results. In 1900 Hugo de Vries and Carl Correns independently reached similar findings and drew attention to his paper. Erich von Tschermak is often named as a third rediscoverer, though historians question whether he understood Mendel's ratios. |
| Gregor Mendel | Not overcome | He died in 1884 without recognition for his work on heredity. After he became abbot in 1868, administrative duties and a long dispute with the government over taxes on the monastery largely ended his research. |
| George Washington Carver | Barrier | He was born enslaved in Diamond Grove, Missouri, and was kidnapped as an infant with his mother. |
| George Washington Carver | Helped | His former enslavers. Moses and Susan Carver, who had owned his mother, raised him after the kidnapping and Emancipation. |
| George Washington Carver | Helped | A college that accepted him. Simpson College in Iowa admitted him in 1890 after Highland had turned him away. He moved on to Iowa State in 1891, earned a bachelor's degree in agriculture in 1894 and a master's degree in 1896, and was its first Black student and first Black faculty member. |
| George Washington Carver | Helped | Booker T. Washington. Washington invited him to lead agriculture at Tuskegee, where he began in October 1896. |
| Yuan Longping | Helped | Protection from the state. An official in Beijing who had read his paper ordered that he be protected and funded. In his oral autobiography, Yuan says that Xiong Yanheng of the State Science and Technology Commission found his paper and passed it to bureau director Zhao Shiying. With the approval of the Commission's leader Nie Rongzhen, Zhao wrote in May 1966 ordering local officials to support the research. In 1975 the central government committed funds to spread hybrid rice. |
| Yuan Longping | Helped | A national team. In November 1970 his assistant Li Bihu and Feng Keshan, a technician at a farm on Hainan Island, found a wild male-sterile rice plant there, which became the key breeding material. From 1971 the material was shared with more than 20 research units in 13 provinces, and in 1972 hybrid rice became a national priority project. |
| Yuan Longping | Not overcome | He was nominated three times for the Chinese Academy of Sciences but was never elected, although he was elected to the Chinese Academy of Engineering in 1995. |
| Yuan Longping | Note | Hybrid rice was a team achievement. Li Bihu and the farm technician Feng Keshan found the wild plant while Yuan was in Beijing, and in 1973 Zhang Xiancheng's team found the restorer lines that completed the breeding system. The historian Sigrid Schmalzer notes that hybrid rice was developed through a network of peasants, technicians, and scientists, and that Mao-era accounts presented it as "mass science." |
| Mary Engle Pennington | Helped | Supportive faculty. Penn professors used a rarely invoked university statute for "extraordinary cases" to admit her to graduate study, and she earned a doctorate in chemistry in 1895. |
| Mary Engle Pennington | Helped | Harvey Wiley. The chief of the Bureau of Chemistry hired her and, according to the Science History Institute, intervened to keep her in the post. In 1907 she became the first chief of the U.S. Department of Agriculture's Food Research Laboratory. |
| Fritz Haber | Barrier | The leading chemist Walther Nernst publicly criticized his ammonia results. |
| Fritz Haber | Helped | Industry partnership. BASF partnered with him in 1908, and he demonstrated a working ammonia apparatus in 1909. |
| Fritz Haber | Helped | Carl Bosch and Alwin Mittasch. Bosch led the industrial scale-up and Mittasch the catalyst work. The first ammonia synthesis plant opened at Oppau in 1913. |
| Nikolai Vavilov | Helped | Training abroad. He studied with the geneticist William Bateson in Britain in 1913 and 1914. |
| Nikolai Vavilov | Helped | Loyal colleagues. During the Siege of Leningrad, staff of his institute protected the seed collection without eating it. The institute's historian counts more than 20 specialists and scientists who lost their lives, most from starvation (Loskutov, 2021). Counts range from 9 to more than 30 depending on whether they include only scientists or all institute staff. |
| Nikolai Vavilov | Helped | International standing. The Royal Society elected him in 1942, while he was in prison. |
Key figures
| Measure | Value | Source |
|---|---|---|
| People who report feeling lonely | About 1 in 6 worldwide (15.8%) | WHO Commission on Social Connection (2025) |
| Deaths linked to loneliness | An estimated 871,000 per year, about 100 every hour | WHO Commission on Social Connection (2025) |
| Loneliness by group | 21% among adolescents, 24.3% in low-income countries, and 11% in high-income countries | WHO Commission on Social Connection (2025) |
| Survival advantage of strong social relationships | About 50% higher likelihood | Holt-Lunstad et al. (2010) |
| Asch conformity experiments | Judging line lengths alone, people erred under 1% of the time (0.7%). With a unanimous group giving wrong answers, 36.8% of responses conformed, 94 of 123 participants (about 76%) conformed at least once, and 29 of 123 (about 24%) never conformed | Asch (1956) |
| Effect of one dissenting voice in the Asch experiments | When one other person gave the correct answer, conformity dropped to about 5% of trials | Asch (1956) |
| Young people who never had an adult mentor | About 1 in 3 (an estimated 16 million), including about 9 million considered at risk | MENTOR, The Mentoring Effect (2014), nationally representative U.S. survey |
| Postsecondary enrollment among at-risk young people | 45% of those with a mentor vs. 29% of those without. This is a correlation from a survey, not proof that mentoring caused the difference | MENTOR, The Mentoring Effect (2014) |
| In-group favoritism | A meta-analysis of 212 studies found people cooperate more with members of their own group than with outsiders (d = 0.32), and that this reflects favoritism toward the in-group more than hostility toward the out-group | Balliet, Wu, and De Dreu (2014) |
| Partner violence against women | Based on 366 studies covering 2 million women in 161 countries, an estimated 27% of ever-partnered women aged 15 to 49 have experienced physical or sexual violence from a partner, and 13% in the past year. Rates are higher in low-income countries. Childhood abuse and household dysfunction are covered under early-life adversity in the biological key figures | Sardinha et al. (2022) |
| Neighbors' earnings and happiness | In U.S. panel data on 8,944 adults, people whose neighbors earned more reported lower happiness, holding their own income constant. The author found this was not explained by who chose to live where. German data found the opposite for neighbors: once comparisons with coworkers and people of the same sex were accounted for, higher neighborhood income was linked to more happiness, while comparisons with those peers predicted lower wellbeing (Mayraz, Wagner, and Schupp, 2009). Who people compare themselves with appears to matter more than neighbors as such | Luttmer (2005) |
| Partner violence and women's work | Among 1,311 Illinois welfare recipients, recent partner violence was linked to unstable employment over three years, largely through health problems (National Institute of Justice). In Tanzania, women who had been abused earned less than women who had not (World Bank). A Colombian study found the opposite, with partner violence increasing women's employment, possibly as a way to escape (EAFIT seminar abstract). All are observational, so the effect of adult partner violence on achievement is rated C | NIJ, World Bank, EAFIT |
| Trickle-down consumption | Using variation across U.S. states and years, non-rich households exposed to higher top incomes spent a larger share of income, especially on visible goods, reported more financial strain, and lived in states with more personal bankruptcies. Middle-income households might have saved an additional 2.6% to 3.2% of their income by the mid-2000s had top incomes grown at the same rate as median income. The authors judge status-driven spending the most consistent explanation. Other work is mixed: a related study supports such "expenditure cascades" (Frank, Levine, and Dijk, 2014), but a working paper found no effect when comparison groups were defined by census division (Wang, working paper) | Bertrand and Morse (2016) |
References cited on this page
- Bertrand, M., & Morse, A. (2016). Trickle-down consumption. Review of Economics and Statistics, 98(5), 863-879. DOI
- Frank, R. H., Levine, A. S., & Dijk, O. (2014). Expenditure cascades. Review of Behavioral Economics, 1(1-2), 55-73
- Wang, H. (n.d., circa 2019, unpublished). Expenditure cascade hypothesis: no evidence at the level of census divisions. Job market paper, University of Delaware. PDF
- Park, J. (2024). Do expenditure cascades exist? Evidence from Bush administration tax reforms. KDIS Working Paper 24-06, KDI School of Public Policy and Management. KDI School
- Riger, S., & Staggs, S. (2004). Impact of intimate partner violence on women's labor force participation: final report (NCJ 207143). National Institute of Justice
- Vyas, S. (2013). Estimating the association between women's earnings and partner violence: evidence from the 2008-2009 Tanzania National Panel Survey. Women's Voice, Agency, and Participation Research Series No. 2. World Bank
- EAFIT. Intimate partner violence and women's employment: evidence from Colombia (seminar abstract, presenter not named, page no longer online as of October 2026)
- Holt-Lunstad, J., Smith, T. B., & Layton, J. B. (2010). Social relationships and mortality risk: a meta-analytic review. PLoS Medicine, 7(7), e1000316. DOI
- Putnam, R. D. (2000). Bowling Alone. New York: Simon and Schuster.
- Balliet, D., Wu, J., & De Dreu, C. K. W. (2014). Ingroup favoritism in cooperation: a meta-analysis. Psychological Bulletin, 140(6), 1556-1581. Semantic Scholar
- Sardinha, L., Maheu-Giroux, M., Stöckl, H., Meyer, S. R., & García-Moreno, C. (2022). Global, regional, and national prevalence estimates of physical or sexual, or both, intimate partner violence against women in 2018. Lancet, 399(10327), 803-813. DOI02664-7)
- Luttmer, E. F. P. (2005). Neighbors as negatives: relative earnings and well-being. Quarterly Journal of Economics, 120(3), 963-1002. DOI
- Mayraz, G., Wagner, G. G., & Schupp, J. (2009). Life satisfaction and relative income: perceptions and evidence. CEP Discussion Paper 938, Centre for Economic Performance, London School of Economics. LSE Research Online
- Asch, S. E. (1956). Studies of independence and conformity: I. A minority of one against a unanimous majority. Psychological Monographs, 70(9), Whole No. 416, 1-70. DOI
- Janis, I. L. (1972). Victims of Groupthink. Boston: Houghton Mifflin.
- Tajfel, H., & Turner, J. C. (1979). An integrative theory of intergroup conflict. In W. G. Austin and S. Worchel (Eds.), The Social Psychology of Intergroup Relations (pp. 33-47). Monterey, CA: Brooks/Cole.
- MENTOR: The Mentoring Effect, executive summary (2014)
Sources for the actions
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- Cabinet Office of Japan. (2025). Priority plan for measures for loneliness and isolation [English version]. link B Moderate
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- De Freitas, J., Uguralp, A. K., Uguralp, Z. O., & Puntoni, S. (2024). AI companions reduce loneliness (arXiv:2407.19096). arXiv. link C Limited
- Fang, C. M., Liu, A. R., Danry, V., Lee, E., Chan, S. W. T., Pataranutaporn, P., et al. (2025). How AI and human behaviors shape psychosocial effects of extended chatbot use: A longitudinal randomized controlled study (arXiv:2503.17473, version 2). arXiv. link C Limited
- Gilbody, S., Littlewood, E., McMillan, D., Atha, L., Bailey, D., Baird, K., et al. (2024). Behavioural activation to mitigate the psychological impacts of COVID-19 restrictions on older people in England and Wales (BASIL+): A pragmatic randomised controlled trial. The Lancet Healthy Longevity, 5(2), e97-e107. link B Moderate
- Kahlon, M. K., Aksan, N., Aubrey, R., Clark, N., Cowley-Morillo, M., Jacobs, E. A., et al. (2021). Effect of layperson-delivered, empathy-focused program of telephone calls on loneliness, depression, and anxiety among adults during the COVID-19 pandemic: A randomized clinical trial. JAMA Psychiatry, 78(6), 616-622. link B Moderate
- Padilla, S. (2025, October 13). First-in-nation AI chatbot safeguards signed into law [Press release]. California State Senate. link B Moderate
- UK Government. (2018, January 17). PM commits to government-wide drive to tackle loneliness [Press release]. link B Moderate
- Becker, J., Brackbill, D., & Centola, D. (2017). Network dynamics of social influence in the wisdom of crowds. Proceedings of the National Academy of Sciences, 114(26), E5070-E5076. link B Moderate
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- Columbia Accident Investigation Board. (2003). Columbia Accident Investigation Board report: Volume 1. National Aeronautics and Space Administration. link B Moderate
- Congressional Research Service. (2003, September 2). NASA's Space Shuttle Columbia: Synopsis of the report of the Columbia Accident Investigation Board (RS21606). link B Moderate
- Gill, C. R., & Epstein, S. B. (2017, April 7). The U.S. Department of State's "Dissent Channel" (CRS In Focus IF10631). Congressional Research Service. link B Moderate
- Lorenz, J., Rauhut, H., Schweitzer, F., & Helbing, D. (2011). How social influence can undermine the wisdom of crowd effect. Proceedings of the National Academy of Sciences, 108(22), 9020-9025. link C Limited
- Nemeth, C., Brown, K., & Rogers, J. (2001). Devil's advocate versus authentic dissent: Stimulating quantity and quality. European Journal of Social Psychology, 31(6), 707-720. link C Limited
- Chang, E. H., Milkman, K. L., Gromet, D. M., Rebele, R. W., Massey, C., Duckworth, A. L., et al. (2019). The mixed effects of online diversity training. Proceedings of the National Academy of Sciences, 116(16), 7778-7783. link B Moderate
- Lai, C. K., Skinner, A. L., Cooley, E., Murrar, S., Brauer, M., Devos, T., et al. (2016). Reducing implicit racial preferences: II. Intervention effectiveness across time. Journal of Experimental Psychology: General, 145(8), 1001-1016. link B Moderate
- Rao, G. (2019). Familiarity does not breed contempt: Generosity, discrimination, and diversity in Delhi schools. American Economic Review, 109(3), 774-809. link B Moderate
- Scacco, A., & Warren, S. S. (2018). Can social contact reduce prejudice and discrimination? Evidence from a field experiment in Nigeria. American Political Science Review, 112(3), 654-677. link B Moderate
- Abramsky, T., Devries, K., Kiss, L., Nakuti, J., Kyegombe, N., Starmann, E., et al. (2014). Findings from the SASA! Study: A cluster randomized controlled trial to assess the impact of a community mobilization intervention to prevent violence against women and reduce HIV risk in Kampala, Uganda. BMC Medicine, 12, 122. link C Limited
- Arce, R., Arias, E., Novo, M., & Fariña, F. (2020). Are interventions with batterers effective? A meta-analytical review. Psychosocial Intervention, 29(3), 153-164. link C Limited
- Babcock, J. C., Green, C. E., & Robie, C. (2004). Does batterers' treatment work? A meta-analytic review of domestic violence treatment. Clinical Psychology Review, 23(8), 1023-1053. link C Limited: (changed from B on October 8, 2026, because a later meta-analysis reached different conclusions on effect size and program type, leaving the size of effects unresolved)
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