Editing Psychology (section)

== Applications ==
{{further|Outline of psychology|List of psychology disciplines|Applied psychology|Subfields of psychology}}
Psychology encompasses many subfields and includes different approaches to the study of mental processes and behavior.

=== Psychological testing ===
{{see also|Psychometrics|social statistics}}
[[File:Francis Galton 1850s.jpg|thumb|[[Francis Galton]], a pioneer of the experimental psychology field]]
Psychological testing has ancient origins, dating as far back as 2200 BC, in the [[imperial examination|examinations for the Chinese civil service]]. Written exams began during the [[Han dynasty]] (202 BC – AD 220). By 1370, the Chinese system required a stratified series of tests, involving essay writing and knowledge of diverse topics. The system was ended in 1906.{{r|Gregory 2011|pp=41-2}} In Europe, mental assessment took a different approach, with theories of [[physiognomy]]—judgment of character based on the face—described by Aristotle in 4th century BC Greece. Physiognomy remained current through the Enlightenment, and added the doctrine of phrenology: a study of mind and intelligence based on simple assessment of neuroanatomy.{{r|Gregory 2011|pp=42-3}}

When experimental psychology came to Britain, Francis Galton was a leading practitioner. By virtue of his procedures for measuring reaction time and sensation, he is considered an inventor of modern mental testing (also known as ''[[psychometrics]]'').{{r|Gregory 2011|pp=44-5}} James McKeen Cattell, a student of Wundt and Galton, brought the idea of psychological testing to the United States, and in fact coined the term "mental test".{{r|Gregory 2011|pp=45-6}} In 1901, Cattell's student [[Clark Wissler]] published discouraging results, suggesting that mental testing of Columbia and Barnard students failed to predict academic performance.{{r|Gregory 2011|pp=45-6}} In response to 1904 orders from the [[Ministry of National Education (France)|Minister of Public Instruction]], One example of an observational study was run by Arthur Bandura. This observational study focused on children who were exposed to an adult exhibiting aggressive behaviors and their reaction to toys versus other children who were not exposed to these stimuli. The result shows that children who had seen the adult acting aggressively towards a toy, in turn, were aggressive towards their own toy when put in a situation that frustrated them.<ref name=":0">Myers, D. G., & DeWall, C. N. (2023). *Psychology in everyday life* (6th ed.). Worth.</ref> psychologists [[Alfred Binet]] and [[Théodore Simon]] developed and elaborated a new test of intelligence in 1905–1911. They used a range of questions diverse in their nature and difficulty. Binet and Simon introduced the concept of [[mental age]] and referred to the lowest scorers on their test as ''[[idiot]]s''. [[Henry H. Goddard]] put the Binet-Simon scale to work and introduced classifications of mental level such as ''imbecile'' and ''feebleminded''. In 1916, (after Binet's death), Stanford professor [[Lewis M. Terman]] modified the Binet-Simon scale (renamed the [[Stanford–Binet Intelligence Scales|Stanford–Binet scale]]) and introduced the [[intelligence quotient]] as a score report.{{r|Gregory 2011|pp=50-56}} Based on his test findings, and reflecting the racism common to that era, Terman concluded that intellectual disability "represents the level of intelligence which is very, very common among Spanish-Indians and Mexican families of the Southwest and also among negroes. Their dullness seems to be racial."<ref name="Guthrie1998Chapter3">Guthrie, ''Even the Rat was White'' (1998), Chapter 3: "Psychometric Scientism" (pp. 55–87)</ref>

Following the Army Alpha and Army Beta tests, which was developed by psychologist [[Robert Yerkes]] in 1917 and then used in World War 1 by industrial and organizational psychologists for large-scale employee testing and selection of military personnel.<ref>{{Cite web|title=Army Alpha and Beta tests|url=https://www.oxfordreference.com/view/10.1093/oi/authority.20110803095424949|access-date=2022-01-18|website=Oxford Reference|language=en|archive-date=19 January 2022|archive-url=https://web.archive.org/web/20220119011118/https://www.oxfordreference.com/view/10.1093/oi/authority.20110803095424949|url-status=live}}</ref> Mental testing also became popular in the U.S., where it was applied to schoolchildren. The federally created National Intelligence Test was administered to 7 million children in the 1920s. In 1926, the [[College Entrance Examination Board]] created the [[Scholastic Aptitude Test]] to standardize college admissions.{{r|Gregory 2011|p=61}} The results of intelligence tests were used to argue for segregated schools and economic functions, including the preferential training of Black Americans for manual labor. These practices were criticized by Black intellectuals such a [[Horace Mann Bond]] and [[Allison Davis (anthropologist)|Allison Davis]].<ref name=Guthrie1998Chapter3 /> Eugenicists used mental testing to justify and organize compulsory sterilization of individuals classified as mentally retarded (now referred to as ''[[intellectual disability]]'').<ref name=GuthrieChapter4 /> In the United States, tens of thousands of men and women were sterilized. Setting a precedent that has never been overturned, the U.S. Supreme Court affirmed the constitutionality of this practice in the 1927 case ''[[Buck v. Bell]]''.<ref>{{cite journal | last1 = Berry | first1 = Robert M. | title = From Involuntary Sterilization to Genetic Enhancement: The Unsettled Legacy of Buck v. Bell | url = http://scholarship.law.nd.edu/ndjlepp/vol12/iss2/3/ | journal = Notre Dame Journal of Law, Ethics & Public Policy | volume = 12 | year = 2012 | access-date = 24 April 2015 | archive-date = 4 March 2016 | archive-url = https://web.archive.org/web/20160304043102/http://scholarship.law.nd.edu/ndjlepp/vol12/iss2/3/ | url-status = live }}</ref>

Today mental testing is a routine phenomenon for people of all ages in Western societies.{{r|Gregory 2011|p=2|q=From birth to old age, we encounter tests at almost every turning point in life. ... Tests are used in almost every nation on earth for counseling, selection, and placement. Testing occurs in settings as diverse as schools, civil service, industry, medical clinics, and counseling centers. Most persons have taken dozens of tests and thought nothing of it. Yet, by the time the typical individual reaches retirement age, it is likely that psychological test results will have helped to shape his or her destiny.}} Modern testing aspires to criteria including standardization of procedure, [[reliability (psychometrics)|consistency of results]], output of an interpretable score, statistical norms describing population outcomes, and, ideally, [[test validity|effective prediction]] of behavior and life outcomes outside of testing situations.{{r|Gregory 2011|pp=4-6}} Psychological testing is regularly used in forensic contexts to aid legal judgments and decisions.<ref>{{Cite journal |last=Neal |first=Tess M.S. |date=2018 |title=Forensic psychology and correctional psychology: Distinct but related subfields of psychological science and practice. |url=http://doi.apa.org/getdoi.cfm?doi=10.1037/amp0000227 |journal=American Psychologist |language=en |volume=73 |issue=5 |pages=651–662 |doi=10.1037/amp0000227 |pmid=29431456 |s2cid=46817929 |issn=1935-990X|hdl=2286/R.I.50913 |hdl-access=free }}</ref> Developments in psychometrics include work on test and scale [[Reliability (statistics)|reliability]] and [[test validity|validity]].<ref>Nunnally, J. C., & Bernstein, I. H. (1994). ''Psychometric theory, 3rd ed.'', New York: McGraw-Hill.</ref> Developments in [[item-response theory]],<ref>Embretson, S.E., & Reise, S.P. (2000). ''Item Response Theory for Psychologists''. Mahwah, NJ: Erlbaum.</ref> [[structural equation modeling]],<ref>Kline, R. B. (2016). ''Principles and practice of structural equation modeling, 4th ed.''New York: Guilford Press.</ref> and bifactor analysis<ref>Rodriguez, A., Reise, S. P., & Haviland, M. G. (2016). Evaluating bifactor models: Calculating and interpreting statistical indices. ''Psychological Methods, 21'', 137–150. http://dx.doi.org/10.1037/met0000045 {{Webarchive|url=https://web.archive.org/web/20200728095730/https://doi.apa.org/doiLanding?doi=10.1037%2Fmet0000045 |date=28 July 2020 }}</ref> have helped in strengthening test and scale construction.

=== Mental health care ===
{{see also|Clinical psychology}}
The provision of psychological health services is generally called clinical psychology in the U.S. Sometimes, however, members of the school psychology and counseling psychology professions engage in practices that resemble that of clinical psychologists. Clinical psychologists typically include people who have graduated from doctoral programs in clinical psychology. In Canada, some of the members of the abovementioned groups usually fall within the larger category of [[professional psychology]]. In Canada and the U.S., practitioners get bachelor's degrees and doctorates; doctoral students in clinical psychology usually spend one year in a predoctoral internship and one year in postdoctoral internship. In Mexico and most other Latin American and European countries, psychologists do not get bachelor's and doctoral degrees; instead, they take a three-year professional course following high school.<ref name=HallHurley /> Clinical psychology is at present the largest specialization within psychology.<ref name=StrickerWidiger /> It includes the study and application of psychology for the purpose of understanding, preventing, and relieving psychological distress, dysfunction, and/or [[mental illness]]. Clinical psychologists also try to promote subjective well-being and personal growth. Central to the practice of clinical psychology are psychological assessment and psychotherapy although clinical psychologists may also engage in research, teaching, consultation, forensic testimony, and program development and administration.<ref name="brain">Brain, Christine. (2002). ''Advanced psychology: applications, issues and perspectives.'' Cheltenham: Nelson Thornes. {{ISBN|0-17-490058-9}}</ref>

Credit for the first psychology clinic in the United States typically goes to [[Lightner Witmer]], who established his practice in Philadelphia in 1896. Another modern psychotherapist was [[Morton Prince]], an early advocate for the establishment of psychology as a clinical and academic discipline.<ref name=StrickerWidiger>George Stricker & Thomas A. Widiger, "Volume Preface", in Weiner (ed.), ''Handbook of Psychology'' (2003), Volume 8: ''Clinical Psychology''.</ref> In the first part of the twentieth century, most mental health care in the United States was performed by psychiatrists, who are medical doctors. Psychology entered the field with its refinements of mental testing, which promised to improve the diagnosis of mental problems. For their part, some psychiatrists became interested in using [[psychoanalysis]] and other forms of [[psychodynamic psychotherapy]] to understand and treat the mentally ill.<ref name=Tomes2008 /><ref>[[Nancy McWilliams]] and Joel Weinberger, "Psychodynamic Psychotherapy", in Weiner (ed.), ''Handbook of Psychology'' (2003), Volume 8: ''Clinical Psychology''.</ref>

Psychotherapy as conducted by psychiatrists blurred the distinction between psychiatry and psychology, and this trend continued with the rise of [[Community mental health service|community mental health facilities]]. Some in the clinical psychology community adopted [[behavioral therapy]], a thoroughly non-psychodynamic model that used behaviorist learning theory to change the actions of patients. A key aspect of behavior therapy is empirical evaluation of the treatment's effectiveness. In the 1970s, [[cognitive-behavior therapy]] emerged with the work of [[Albert Ellis]] and [[Aaron Beck]]. Although there are similarities between behavior therapy and cognitive-behavior therapy, cognitive-behavior therapy required the application of cognitive constructs. Since the 1970s, the popularity of cognitive-behavior therapy among clinical psychologists increased. A key practice in behavioral ''and'' cognitive-behavioral therapy is exposing patients to things they fear, based on the premise that their responses (fear, panic, anxiety) can be deconditioned.<ref>W. Edward Craighead & Linda Wilcoxon Craighead, "Behavioral and Cognitive-Behavioral Psychotherapy" in Weiner (ed.), ''Handbook of Psychology'' (2003), Volume 8: ''Clinical Psychology''.</ref>

Mental health care today involves psychologists and social workers in increasing numbers. In 1977, National Institute of Mental Health director [[Bertram S. Brown|Bertram Brown]] described this shift as a source of "intense competition and role confusion."<ref name=Tomes2008>Nancy Tomes, "The Development of Clinical Psychology, Social Work, and Psychiatric Nursing: 1900–1980s", in Wallace & Gach (eds.), ''History of Psychiatry and Medical Psychology'' (2008).</ref> Graduate programs issuing doctorates in clinical psychology emerged in the 1950s and underwent rapid increase through the 1980s. The PhD degree is intended to train practitioners who could also conduct scientific research. The PsyD degree is more exclusively designed to train practitioners.<ref name=HallHurley />

Some clinical psychologists focus on the clinical management of patients with brain injury. This subspecialty is known as [[clinical neuropsychology]]. In many countries, clinical psychology is a regulated mental health profession. The emerging field of ''disaster psychology'' (see [[crisis intervention]]) involves professionals who respond to large-scale traumatic events.<ref>Teri L. Elliott, "Disaster Psychology: Keep Clients out of Your Office—Get into the Field!" in Morgan et al. (ed.), ''Life After Graduate School in Psychology'' (2005). "...it is the disaster psychologist's role to utilize crisis intervention processes with the goal of preventing natural distress due to the critical event from developing into a more harmful, long-term psychological condition."</ref>

The work performed by clinical psychologists tends to be influenced by various therapeutic approaches, all of which involve a formal relationship between professional and client (usually an individual, couple, family, or small group). Typically, these approaches encourage new ways of thinking, feeling, or behaving. Four major theoretical perspectives are psychodynamic, cognitive behavioral, existential–humanistic, and systems or family therapy. There has been a growing movement to integrate the various therapeutic approaches, especially with an increased understanding of issues regarding culture, gender, spirituality, and sexual orientation. With the advent of more robust research findings regarding psychotherapy, there is evidence that most of the major therapies have equal effectiveness, with the key common element being a strong [[therapeutic relationship|therapeutic alliance]].<ref>{{cite journal |author1=Leichsenring, Falk |author2=Leibing, Eric |year=2003 |title=The effectiveness of psychodynamic therapy and cognitive behavior therapy in the treatment of personality disorders: A meta-analysis |journal=The American Journal of Psychiatry |volume=160 |issue=7 |pages=1223–1233 |doi=10.1176/appi.ajp.160.7.1223 |pmid=12832233}}</ref><ref>{{cite journal |author=Reisner, Andrew |year=2005 |title=The common factors, empirically validated treatments, and recovery models of therapeutic change |journal=The Psychological Record |volume=55 |issue=3 |pages=377–400 |doi=10.1007/BF03395517 |s2cid=142840311 |url=https://opensiuc.lib.siu.edu/cgi/viewcontent.cgi?article=1192&context=tpr |access-date=21 July 2019 |archive-date=6 August 2020 |archive-url=https://web.archive.org/web/20200806165820/https://opensiuc.lib.siu.edu/cgi/viewcontent.cgi?article=1192&context=tpr |url-status=dead }}</ref> Because of this, more training programs and psychologists are now adopting an [[Integrative Psychotherapy|eclectic therapeutic orientation]].<ref>{{cite journal |author1=Jensen, J.P. |author2=Bergin, A.E. |author3=Greaves, D.W. |year=1990 |title=The meaning of eclecticism: New survey and analysis of components |journal=Professional Psychology: Research and Practice |volume=21 |issue=2 |pages=124–130 |doi=10.1037/0735-7028.21.2.124}}</ref><ref>Palmer, S.; Woolfe, R. (eds.) (1999). ''Integrative and eclectic counselling and psychotherapy.'' London: Sage.</ref><ref>Clarkson, P. (1996). The eclectic and integrative paradigm: Between the Scylla of confluence and the Charybdis of confusion. In ''Handbook of Counselling Psychology'' (R. Woolfe & W.L. Dryden, eds.). London: Sage, pp. 258–283. {{ISBN|0-8039-8991-1}}</ref><ref>{{cite journal |author1=Goldfried, M.R. |author2=Wolfe, B.E. |year=1998 |title=Toward a more clinically valid approach to therapy research |journal=Journal of Consulting and Clinical Psychology |volume=66 |issue=1 |pages=143–150 |doi=10.1037/0022-006X.66.1.143 |pmid=9489268 |url=http://www.personal.kent.edu/~dfresco/CRM_Readings/Goldfried_1998.pdf |citeseerx=10.1.1.475.7156 |access-date=25 October 2017 |archive-date=9 August 2017 |archive-url=https://web.archive.org/web/20170809053356/http://www.personal.kent.edu/~dfresco/CRM_Readings/Goldfried_1998.pdf |url-status=live }}</ref><ref>{{cite journal |author=Seligman, M.E.P. |year=1995 |title=The effectiveness of psychotherapy: The ''Consumer Reports'' study |journal=American Psychologist |volume=50 |issue=12 |pages=965–974 |doi=10.1037/0003-066X.50.12.965 |pmid=8561380 |url=http://www.dearshrink.com/psychotherapy_consumer_report1995_seligman.pdf |access-date=25 October 2017 |archive-date=21 July 2018 |archive-url=https://web.archive.org/web/20180721231945/http://www.dearshrink.com/psychotherapy_consumer_report1995_seligman.pdf |url-status=dead }}</ref>

Diagnosis in clinical psychology usually follows the ''Diagnostic and Statistical Manual of Mental Disorders'' (DSM).<ref>Peter E. Nathan & James Langenbucher, "Diagnosis and Classification", in Weiner (ed.), ''Handbook of Psychology'' (2003), Volume 8: ''Clinical Psychology''.</ref> The study of mental illnesses is called [[abnormal psychology]].

=== Education ===
{{Main|Educational psychology|School psychology}}
[[File:Figural Relationships.svg|right|thumb|An item from a cognitive abilities test used in [[educational psychology]]]]
Educational psychology is the study of how humans learn in educational settings, the effectiveness of educational interventions, the psychology of teaching, and the social psychology of schools as organizations. Educational psychologists can be found in preschools, schools of all levels including post secondary institutions, community organizations and learning centers, Government or private research firms, and independent or private consultant.<ref>{{Cite web|title=What Does An Educational Psychologist Do {{!}} Touro University {{!}} Psychology|url=https://www.tuw.edu/program-resources/educational-psychologist/|access-date=30 September 2021|website=Touro University WorldWide|date=29 July 2014 |language=en-US|archive-date=30 September 2021|archive-url=https://web.archive.org/web/20210930210235/https://www.tuw.edu/program-resources/educational-psychologist/|url-status=live}}</ref> The work of developmental psychologists such as Lev Vygotsky, [[Jean Piaget]], and [[Jerome Bruner]] has been influential in creating teaching methods and educational practices. Educational psychology is often included in teacher education programs in places such as North America, Australia, and New Zealand.

School psychology combines principles from educational psychology and clinical psychology to understand and treat students with learning disabilities; to foster the intellectual growth of [[intellectual giftedness|gifted]] students; to facilitate [[prosocial behavior]]s in adolescents; and otherwise to promote safe, supportive, and effective learning environments. School psychologists are trained in educational and behavioral assessment, intervention, prevention, and consultation, and many have extensive training in research.<ref>{{cite web|author=National Association of School Psychologists |title=Who are school psychologists? |url=http://nasponline.org/about_sp/whatis.aspx |access-date=1 June 2008 |url-status=dead |archive-url=https://web.archive.org/web/20080517055058/http://nasponline.org/about_sp/whatis.aspx |archive-date=17 May 2008 }}</ref>

=== Work ===
{{see also|Industrial and organizational psychology|Organizational behavior}}
Industrial and organizational (I/O) psychology involves research and practices that apply psychological theories and principles to organizations and individuals' work-lives.<ref>Truxillo, D. M., Bauer, T. N., & Erdogan, B. (2016). ''Psychology and work: Perspectives on industrial and organizational psychology''. New York: Psychology Press. {{ISBN|1134705697}}</ref> In the field's beginnings, industrialists brought the nascent field of psychology to bear on the study of [[scientific management]] techniques for improving workplace efficiency. The field was at first called ''economic psychology'' or ''business psychology''; later, ''industrial psychology'', ''employment psychology'', or ''psychotechnology''.<ref name=Koppes>Laura L. Koppes, "Industrial-Organizational Psychology", in Weiner (ed.), ''Handbook of Psychology'' (2003), Volume 1: ''History of Psychology''.</ref> An influential early study examined workers at Western Electric's Hawthorne plant in Cicero, Illinois from 1924 to 1932. Western Electric experimented on factory workers to assess their responses to changes in illumination, breaks, food, and wages. The researchers came to focus on workers' responses to observation itself, and the term [[Hawthorne effect]] is now used to describe the fact that people's behavior can change when they think they are being observed.<ref>Yeh Hsueh, "The Hawthorne experiments and the introduction of Jean Piaget in American industrial psychology, 1929–1932"; ''History of Psychology'' 5.2, May 2002.</ref> Although the Hawthorne research can be found in psychology textbooks, the research and its findings were weak at best.<ref>{{cite journal |first=H. M. |last=Parsons |year=1974 |title=What happened at Hawthorne?: New evidence suggests the Hawthorne effect resulted from operant reinforcement contingencies |journal=Science |volume=183 |issue=4128 |pages=922–932 |doi=10.1126/science.183.4128.922 |pmid=17756742  |s2cid=38816592 }}</ref><ref>{{cite journal |last1=Levitt |first1=Steven D. |last2=List |first2=John A. |year=2011 |title=Was There Really a Hawthorne Effect at the Hawthorne Plant? An Analysis of the Original Illumination Experiments |journal=American Economic Journal: Applied Economics |volume=3 |issue=1 |pages=224–238 |doi=10.1257/app.3.1.224 |s2cid=16678444 |url=http://www.nber.org/papers/w15016.pdf |access-date=9 June 2021 |archive-date=2 June 2018 |archive-url=https://web.archive.org/web/20180602152530/http://www.nber.org/papers/w15016.pdf |url-status=live }}</ref>

The name industrial and organizational psychology emerged in the 1960s. In 1973, it became enshrined in the name of the [[Society for Industrial and Organizational Psychology]], Division 14 of the American Psychological Association.<ref name=Koppes /> One goal of the discipline is to optimize human potential in the workplace. Personnel psychology is a subfield of I/O psychology. Personnel psychologists apply the methods and principles of psychology in selecting and evaluating workers. Another subfield, [[organizational psychology]], examines the effects of work environments and management styles on worker motivation, job satisfaction, and productivity.<ref>Myers (2004). Motivation and work. ''Psychology''. New York, NY: Worth Publishers</ref> Most I/O psychologists work outside of academia, for private and public organizations and as consultants.<ref name=Koppes /> A psychology consultant working in business today might expect to provide executives with information and ideas about their industry, their target markets, and the organization of their company.<ref>Steven Williams, "Executive Management: Helping Executives Manage Their Organizations through Organizational and Market Research" in Morgan et al. (ed.), ''Life After Graduate School in Psychology'' (2005).</ref><ref>See also for example Baden Eunson: ''Behaving – Managing Yourself and Others.'' [[S&P Global|McGraw-Hill]], Sidney/New York City 1987, {{ISBN|978-0-0745-2022-2}}.</ref>

Organizational behavior (OB) is an allied field involved in the study of human behavior within organizations.<ref>Moorhead, G., & Griffin, R. W. (2017). ''Organizational behavior: Managing people and organizations, 12th ed.''. Boston: Cengage. {{ISBN|978-1-305-50139-3}}</ref> One way to differentiate I/O psychology from OB is that I/O psychologists train in university psychology departments and OB specialists, in business schools.

=== Military and intelligence ===
One role for [[military psychology|psychologists in the military]] has been to evaluate and counsel soldiers and other personnel. In the U.S., this function began during World War I, when Robert Yerkes established the School of Military Psychology at [[Fort Oglethorpe, Georgia|Fort Oglethorpe]] in Georgia. The school provided psychological training for military staff.<ref name=Tomes2008 /><ref>[[Robert M. Yerkes]], "[http://www.pnas.org/content/4/10/295.full.pdf Measuring the Mental Strength of an Army] {{Webarchive|url=https://web.archive.org/web/20170120194554/http://www.pnas.org/content/4/10/295.full.pdf |date=20 January 2017 }}"; ''Proceedings of the National Academy of Sciences'' 4.10, 15 October 1918.</ref> Today, U.S. Army psychologists perform psychological screening, clinical psychotherapy, [[suicide prevention]], and treatment for post-traumatic stress, as well as provide prevention-related services, for example, smoking cessation.<ref>Joshua N. Friedlander, "Military Psychology: An Army Clinical Psychologist" in Morgan et al. (ed.), ''Life After Graduate School in Psychology'' (2005).</ref> The United States Army's Mental Health Advisory Teams implement psychological interventions to help combat troops experiencing mental problems.<ref>Thomas, J.L. (2008). OHP Research and Practice in the US Army: Mental Health Advisory Teams. ''Newsletter of the Society for Occupational Health Psychology, 4'', 4–5. [https://sohp-online.org/wp-content/uploads/2019/04/sohpnewsletterv04-october2008.pdf] {{Webarchive|url=https://web.archive.org/web/20211104142222/https://sohp-online.org/wp-content/uploads/2019/04/sohpnewsletterv04-october2008.pdf|date=4 November 2021}}</ref><ref>Genderson, M.R., Schonfeld, I.S., Kaplan, M.S., & Lyons, M.J. (2009).Suicide associated with military service. ''Newsletter of the Society for Occupational Health Psychology, 6'', 5–7. [https://sohp-online.org/wp-content/uploads/2019/04/sohpnewsletterv06-may2009.pdf] {{Webarchive|url=https://web.archive.org/web/20170922004626/http://www.sohp-online.org/NewsletterDownloads/SOHPNewsletterV6May2009.pdf|date=22 September 2017}}</ref>

Psychologists may also work on a diverse set of campaigns known broadly as psychological warfare. Psychological warfare chiefly involves the use of propaganda to influence enemy soldiers and civilians. This so-called black propaganda is designed to seem as if it originates from a source other than the Army.<ref>[[Cordwainer Smith|Paul M.A. Linebarger]], ''Psychological Warfare''; Washington: Combat Forces Press, 1954.</ref> The [[CIA]]'s [[MKULTRA]] program involved more individualized efforts at [[Brainwashing|mind control]], involving techniques such as hypnosis, torture, and covert involuntary administration of [[LSD]].<ref>See "[https://www.nytimes.com/packages/pdf/national/13inmate_ProjectMKULTRA.pdf Project MKULTRA, the CIA's Program of Research in Behavioral Modification] {{Webarchive|url=https://web.archive.org/web/20110429194235/http://www.nytimes.com/packages/pdf/national/13inmate_ProjectMKULTRA.pdf |date=29 April 2011 }}"; Joint Hearing before the Senate Committee on Intelligence and the Subcommittee on Health and Scientific Research of the Committee on Human Resources, United States Senate, Ninety Fifth Congress, First Session, 3 August 1997; and [[John D. Marks]], ''The Search for the Manchurian Candidate'', New York: Times Books, 1979.</ref> The U.S. military used the name [[Psychological Operations (United States)|Psychological Operations]] (PSYOP) until 2010, when these activities were reclassified as Military Information Support Operations (MISO), part of [[Information Operations (United States)|Information Operations]] (IO).<ref>Alfred Paddock, Jr., "[http://oai.dtic.mil/oai/oai?verb=getRecord&metadataPrefix=html&identifier=ADA523696 PSYOP: On a Complete Change in Organization, Practice, and Doctrine] {{Webarchive|url=https://web.archive.org/web/20150712195716/http://oai.dtic.mil/oai/oai?verb=getRecord&metadataPrefix=html&identifier=ADA523696 |date=12 July 2015 }}", ''Small Wars Journal'' 2010.</ref> Psychologists have sometimes been involved in assisting the interrogation and torture of suspects, staining the records of the psychologists involved.<ref>[https://www.theguardian.com/us-news/2015/jul/11/cia-torture-doctors-psychologists-apa-prosecution US torture report: psychologists should no longer aid military, group says] {{Webarchive|url=https://web.archive.org/web/20161214080507/https://www.theguardian.com/us-news/2015/jul/11/cia-torture-doctors-psychologists-apa-prosecution |date=14 December 2016 }} ''The Guardian'', 11 July 2015</ref>

=== Health, well-being, and social change ===
{{see also|Health psychology|Social issues|Occupational health psychology}}

====Social change====
An example of the contribution of psychologists to social change involves the research of [[Kenneth B. Clark|Kenneth]] and [[Mamie Phipps Clark]]. These two African American psychologists studied segregation's adverse psychological impact on Black children. Their research findings played a role in the desegregation case ''[[Brown v. Board of Education]]'' (1954).<ref>Guthrie, ''Even the Rat was White'' (1998), Chapter 7: "Production of Black Psychologists in America" (pp. 155–213).</ref>

The impact of psychology on social change includes the discipline's broad influence on teaching and learning. Research has shown that compared to the "whole word" or "whole language" approach, the phonics approach to reading instruction is more efficacious.<ref>Chall, J. S. (1995). ''Learning to read: The great debate'', 3rd ed. Fort Worth: Harcourt Brace.</ref>

====Medical applications====
Medical facilities increasingly employ psychologists to perform various roles. One aspect of health psychology is the [[psychoeducation]] of patients: instructing them in how to follow a medical regimen. Health psychologists can also educate doctors and conduct research on patient compliance.<ref>Marilu Price Berry, "Interdisciplinary Medical Setting: The Multiple Roles of a Health Psychologist" in Morgan et al. (ed.), ''Life After Graduate School in Psychology'' (2005).</ref><ref>Robiner, W. N., & Seime, R. J. (2008). Psychologists in academic health centers: Traditions and innovations in education, science, and practice. ''Journal of Clinical Psychology in Medical Settings, 15'', 3–6. {{doi|10.1007/s10880-008-9091-1}}</ref> Psychologists in the field of public health use a wide variety of interventions to influence human behavior. These range from public relations campaigns and outreach to governmental laws and policies. Psychologists study the composite influence of all these different tools in an effort to influence whole populations of people.<ref>Monica L. Baskin, "Public Health: Career Opportunities for Psychologists in Public Health", in Morgan et al. (ed.), ''Life After Graduate School in Psychology'' (2005). "Prevention strategies of late have largely concentrated on community-based interventions, which have been shown to be effective in changing the health of large populations. Behavioral and social scientists, such as psychologists, are helpful in this arena as we are trained to view individuals as belonging to complex and dynamic social systems, including immediate and extended family systems, acquaintance and friendship networks, neighborhood and community systems, and cultural groups (Schneiderman & Spee4, 2001)."</ref>

====Worker health, safety and wellbeing====
Psychologists work with organizations to apply findings from psychological research to improve the health and well-being of employees. Some work as external consultants hired by organizations to solve specific problems, whereas others are full-time employees of the organization. Applications include conducting surveys to identify issues and designing interventions to make work healthier. Some of the specific health areas include:
* Accidents and injuries: A major contribution is the concept of [[safety climate]], which is employee shared perceptions of the behaviors that are encouraged (e.g., wearing safety gear) and discouraged (not following safety rules) at work.<ref>{{Cite journal |last=Zohar |first=Dov |date=2010 |title=Thirty years of safety climate research: Reflections and future directions |url=https://linkinghub.elsevier.com/retrieve/pii/S0001457509003339 |journal=Accident Analysis & Prevention |language=en |volume=42 |issue=5 |pages=1517–1522 |doi=10.1016/j.aap.2009.12.019}}</ref> Organizations with strong safety climates have fewer [[work accidents]] and injuries.<ref>Beus, J. M., McCord, M. A., & Zohar, D. (2016). "Workplace safety:A review and research synthesis". ''Organizational Psychology Review'', 6, 352-381. {{doi|10.1177/2041386615626243}}.</ref>
* [[Cardiovascular disease]]: Cardiovascular disease has been related to lack of [[Job control (workplace)|job control]].<ref>{{Cite journal |last1=Clays |first1=Els |last2=De Bacquer |first2=Dirk |last3=Delanghe |first3=Joris |last4=Kittel |first4=France |last5=Van Renterghem |first5=Lieve |last6=De Backer |first6=Guy |date=September 2005 |title=Associations between dimensions of job stress and biomarkers of inflammation and infection |url=https://pubmed.ncbi.nlm.nih.gov/16155472/ |journal=Journal of Occupational and Environmental Medicine |volume=47 |issue=9 |pages=878–883 |doi=10.1097/01.jom.0000171056.22917.ad |issn=1076-2752 |pmid=16155472|hdl=1854/LU-321816 |hdl-access=free }}</ref>
* Mental health: Exposure to [[occupational stress]] is associated with mental health disorder.<ref>Brown, A. D., Schultebraucks, K., Qian, M., Li, M., Horesh, D., Siegel, C., Brody, Y., Amer, A. M., Lev-Ari, R. K., Mas, F., Marmar, C. R., & Farmer, J. (2020). "[https://www.cambridge.org/core/journals/global-mental-health/article/mental-health-disorders-and-utilization-of-mental-healthcare-services-in-united-nations-personnel/45E0B57C295A276E108B22F3E95694FD Mental health disorders and utilization of mental healthcare services in United Nations personnel]". ''Global Mental Health'', 7. {{doi|10.1017/gmh.2019.29}}.</ref>
* [[Musculoskeletal disorder]]: These are injuries in bones, nerves and tendons due to overexertion and repetitive strain. They have been linked to job satisfaction and workplace stress.<ref>Amiri, S., & Behnezhad, S. (2020). "Is job strain a risk factor for musculoskeletal pain? A systematic review and meta-analysis of 21 longitudinal studies". ''Public Health'', 181, 158-167. {{doi|10.1016/j.puhe.2019.11.023}}.</ref>
* Physical health symptoms: Occupational stress has been linked to physical symptoms such as digestive distress and headache.<ref>Nixon, A. E., Mazzola, J. J., Bauer, J., Krueger, J. R., & Spector, P. E. (2011). "Can work make you sick? A meta-analysis of the relationships between job stressors and physical symptoms". ''Work & Stress'', 25, 1-22. {{doi|10.1080/02678373.2011.569175}}.</ref>
* [[Workplace violence]]: Violence prevention climate is related to being physically assaulted and psychologically mistreated at work.<ref>{{Cite journal |last1=Yang |first1=Liu-Qin |last2=Caughlin |first2=David E. |last3=Gazica |first3=Michele W. |last4=Truxillo |first4=Donald M. |last5=Spector |first5=Paul E. |date=July 2014 |title=Workplace mistreatment climate and potential employee and organizational outcomes: A meta-analytic review from the target's perspective. |url=https://doi.apa.org/doi/10.1037/a0036905 |journal=Journal of Occupational Health Psychology |language=en |volume=19 |issue=3 |pages=315–335 |doi=10.1037/a0036905 |pmid=24885687 |issn=1939-1307}}</ref>
Interventions that improve climates are a way to address accidents and violence. Interventions that reduce stress at work or provide employees with tools to better manage it can help in areas where stress is an important component.

Industrial psychology became interested in worker fatigue during World War I, when government ministers in Britain were concerned about the impact of fatigue on workers in munitions factories but not other types of factories.<ref>Hochschild, A. (2011). ''To End All Wars: A Story of Loyalty and Rebellion, 1914–1918''. {{ISBN|978-0-547-75031-6}}.</ref><ref name="Kreis">Kreis, S. (1995). Early experiments in British scientific management: the Health of Munitions Workers' Committee, 1915-1920. ''Journal of Management History (archive), 1'', 65-78. {{doi|10.1108/13552529510088330}}.</ref> In the U. K. some interest in worker [[well-being]] emerged with the efforts of [[Charles Samuel Myers]] and his National Institute of Industrial Psychology (NIIP) during the inter-War years.<ref>Kwiatkowski, R., Duncan, D. C., & Shimmin, S. (2006). "What have we forgotten - and why?" ''Journal of Occupational and Organizational Psychology'', 79(2), 183-201. {{doi|10.1348/096317905X70832}}.</ref> In the U. S. during the mid-twentieth century industrial psychologist [[Arthur Kornhauser]] pioneered the study of occupational mental health, linking industrial working conditions to mental health as well as the spillover of an unsatisfying job into a worker's personal life.<ref name="Zickar">Zickar, M. J. (2003). Remembering Arthur Kornhauser: Industrial psychology's advocate for worker well-being. ''Journal of Applied Psychology, 88'', 363–369. {{doi|10.1037/0021-9010.88.2.363}}</ref><ref>Kornhauser, A. (1965). ''Mental health of the industrial worker''. New York: Wiley.</ref> Zickar accumulated evidence to show that "no other industrial psychologist of his era was as devoted to advocating management and labor practices that would improve the lives of working people."<ref name="Zickar"/>

====Occupational health psychology====
As interest in the worker health expanded toward the end of the twentieth century, the field of [[occupational health psychology]] (OHP) emerged. OHP is a branch of psychology that is interdisciplinary.<ref name="Schonfeld"/><ref name="CDC">Centers for Disease Control and Prevention. ''Occupational Health Psychology (OHP)''. [https://www.cdc.gov/niosh/topics/ohp/] {{Webarchive|url=https://web.archive.org/web/20190910090414/https://www.cdc.gov/niosh/topics/ohp/|date=10 September 2019}}</ref> OHP is concerned with the health and safety of workers.<ref name = "Schonfeld"/><ref name = "CDC"/> OHP addresses topic areas such as the impact of occupational stressors on physical and mental health, mistreatment of workers (e.g., bullying and violence), work-family balance, the impact of [[involuntary unemployment]] on physical and mental health, the influence of psychosocial factors on safety and accidents, and interventions designed to improve/protect worker health.<ref name = "Schonfeld"/><ref>Houdmont, J., & Leka, S. (2010). An introduction to occupational health psychology. In S. Leka & J. Houdmont (Eds.). ''Occupational health psychology'' (pp. 1–30). John Wiley: Hoboken, NJ.</ref> OHP grew out of [[health psychology]], [[industrial and organizational psychology]], and [[occupational medicine]].<ref name = "Everly">Everly, G.S., Jr. (1986). An introduction to occupational health psychology. In P.A. Keller & L.G. Ritt (Eds.), ''Innovations in clinical practice: A source book'' (Vol. 5, pp. 331–338). Sarasota, FL: Professional Resource Exchange.</ref> OHP has also been informed by disciplines outside psychology, including [[industrial engineering]], sociology, and economics.<ref>Society for Occupational Health Psychology. ''Field of OHP. What is occupational health psychology'' [http://www.sohp-online.org/field.htm] {{Webarchive|url=https://web.archive.org/web/20160304192927/http://www.sohp-online.org/field.htm|date=4 March 2016}}</ref><ref>Tetrick, L.E., & Quick, J.C. (2011). Overview of occupational health psychology: Public health in occupational settings. In J.C. Quick & L.E. Tetrick (Eds.), ''Handbook of occupational health psychology'' (2nd ed., pp. 3–20). Washington DC: American Psychological Association.</ref>