{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,3]],"date-time":"2026-06-03T06:38:16Z","timestamp":1780468696096,"version":"3.54.1"},"reference-count":65,"publisher":"BMJ","issue":"8","content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Open"],"accepted":{"date-parts":[[2015,4,27]]},"published-print":{"date-parts":[[2015,8]]},"abstract":"<jats:sec>\n                    <jats:title>Objectives<\/jats:title>\n                    <jats:p>To investigate whether second-to-fourth digit ratio (2D:4D), a measure commonly used as a proxy for fetal testosterone exposure, is associated with autism spectrum disorders (ASDs), as predicted by the extreme male brain theory of autism.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Design<\/jats:title>\n                    <jats:p>A birth cohort study.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Setting<\/jats:title>\n                    <jats:p>The Avon Longitudinal Study of Parents and Children (ALSPAC).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Participants<\/jats:title>\n                    <jats:p>6015 ALSPAC children with data on digit ratio, at least 1 outcome measure and information on potential confounding variables (parental occupational class, maternal education and age at digit ratio measurement). Digit ratio was measured by the photocopy and calliper method.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Outcomes<\/jats:title>\n                    <jats:p>ASD diagnosis (cases were identified previously by record linkage or maternal report) and 4 measures that combine optimally within ALSPAC to predict ASD: the Children's Communication Checklist (coherence subscale), the Social and Communication Disorders Checklist, a repetitive behaviour measure, and the Emotionality, Activity and Sociability scale (sociability subscale). These measures were dichotomised, with approximately 10% defined as the \u2018risk\u2019 group.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Using logistic regression, we examined the association of 2D:4D with ASDs and 4 dichotomised ASD traits. Covariates were occupational class, maternal education and age at 2D:4D measurement. 2D:4D was not associated with ASDs in males (adjusted OR per 1 SD increase in mean 2D:4D, 0.88 (95% CI 0.65 to 1.21), p=0.435) or females (adjusted OR=1.36 (95% CI 0.81 to 2.28), p=0.245). Similar results were observed after adjustment for IQ. There was 1 weak association between reduced coherence and increased left 2D:4D in males, in the opposite direction to that predicted by the extreme male brain theory (adjusted OR=1.15 (95% CI 1.02 to 1.29), p=0.023). Given multiple comparisons, this is consistent with chance.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>In this population-based study, there was no strong evidence of an association between 2D:4D and ASD diagnosis or traits, although the CIs were wide. These results are not consistent with the extreme male brain theory.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1136\/bmjopen-2014-007433","type":"journal-article","created":{"date-parts":[[2015,8,25]],"date-time":"2015-08-25T21:24:53Z","timestamp":1440537893000},"page":"e007433","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":30,"title":["Digit ratio and autism spectrum disorders in the Avon Longitudinal Study of Parents and Children: a birth cohort study"],"prefix":"10.1136","volume":"5","author":[{"given":"Anna Louise","family":"Guyatt","sequence":"first","affiliation":[{"name":"Centre for Academic Mental Health, School of Social and Community Medicine, University of Bristol, Bristol, UK"},{"name":"MRC Integrative Epidemiology Unit, School of Social & Community Medicine, University of Bristol, Bristol, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jon","family":"Heron","sequence":"additional","affiliation":[{"name":"Centre for Academic Mental Health, School of Social and Community Medicine, University of Bristol, Bristol, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bernice Le Cornu","family":"Knight","sequence":"additional","affiliation":[{"name":"Centre for Academic Mental Health, School of Social and Community Medicine, University of Bristol, Bristol, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jean","family":"Golding","sequence":"additional","affiliation":[{"name":"Centre for Child and Adolescent Health, School of Social & Community Medicine, University of Bristol, Bristol, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7239-3523","authenticated-orcid":false,"given":"Dheeraj","family":"Rai","sequence":"additional","affiliation":[{"name":"Centre for Academic Mental Health, School of Social and Community Medicine, University of Bristol, Bristol, UK"},{"name":"Avon and Wiltshire Partnership NHS Mental Health Trust, Bristol, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"239","published-online":{"date-parts":[[2015,8,25]]},"reference":[{"key":"2025121220205486000_5.8.e007433.1","doi-asserted-by":"crossref","unstructured":"American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders (DSM-5) . Arlington, VA: American Psychiatric Publishing, 2013.","DOI":"10.1176\/appi.books.9780890425596"},{"key":"2025121220205486000_5.8.e007433.2","doi-asserted-by":"publisher","DOI":"10.1111\/j.1469-7610.1977.tb00443.x"},{"key":"2025121220205486000_5.8.e007433.3","doi-asserted-by":"crossref","first-page":"50","DOI":"10.3109\/17549507.2013.861511","article-title":"The importance of early identification and intervention for children with or at risk for autism spectrum disorders","volume":"16","author":"Koegel","year":"2014","journal-title":"Int J Speech Lang Pathol"},{"key":"2025121220205486000_5.8.e007433.4","first-page":"1","article-title":"Prevalence of autism spectrum disorder among children aged 8 years\u2014autism and developmental disabilities monitoring network, 11 sites, United States, 2010","volume":"63","author":"Developmental Disabilities Monitoring Network Surveillance Year 2010 Principal Investigators; Centers for Disease Control and Prevention (CDC)","year":"2014","journal-title":"MMWR Surveill Summ"},{"key":"2025121220205486000_5.8.e007433.5","doi-asserted-by":"publisher","DOI":"10.1016\/j.jaac.2011.04.001"},{"key":"2025121220205486000_5.8.e007433.6","doi-asserted-by":"publisher","DOI":"10.1016\/S0140-6736(06)69041-7"},{"key":"2025121220205486000_5.8.e007433.7","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0041280"},{"key":"2025121220205486000_5.8.e007433.8","unstructured":"The NHS Information Centre for Health and Social Care. Autism spectrum disorders in adults living in households throughout England. Report from the Adult Psychiatric Morbidity Survey 2007. http:\/\/www.hscic.gov.uk\/catalogue\/PUB01131\/aut-sp-dis-adu-liv-ho-a-p-m-sur-eng-2007-rep.pdf Published 22 September 2009 (accessed 28 Aug 2014)."},{"key":"2025121220205486000_5.8.e007433.9","doi-asserted-by":"crossref","first-page":"1148","DOI":"10.1016\/j.jaac.2013.08.006","article-title":"Gender differences in the relationship between social communication and emotion recognition","volume":"52","author":"Kothari","year":"2013","journal-title":"J Am Acad Child Adolesc Psychiatry"},{"key":"2025121220205486000_5.8.e007433.10","doi-asserted-by":"publisher","DOI":"10.1016\/j.jaac.2012.05.018"},{"key":"2025121220205486000_5.8.e007433.11","doi-asserted-by":"publisher","DOI":"10.1016\/S1364-6613(02)01904-6"},{"key":"2025121220205486000_5.8.e007433.12","doi-asserted-by":"publisher","DOI":"10.1001\/archneur.1985.04060050026008"},{"key":"2025121220205486000_5.8.e007433.13","doi-asserted-by":"publisher","DOI":"10.1002\/neu.480210511"},{"key":"2025121220205486000_5.8.e007433.14","doi-asserted-by":"publisher","DOI":"10.1038\/mp.2014.48"},{"key":"2025121220205486000_5.8.e007433.15","doi-asserted-by":"publisher","DOI":"10.1017\/S0012162201000317"},{"key":"2025121220205486000_5.8.e007433.16","doi-asserted-by":"publisher","DOI":"10.1192\/bjp.bp.111.097899"},{"key":"2025121220205486000_5.8.e007433.17","doi-asserted-by":"publisher","DOI":"10.1017\/S0012162206002118"},{"key":"2025121220205486000_5.8.e007433.18","doi-asserted-by":"publisher","DOI":"10.1007\/s10803-007-0419-8"},{"key":"2025121220205486000_5.8.e007433.19","first-page":"377","article-title":"2D:4D finger ratio in Slovak autism spectrum disorder population","volume":"112","author":"Krajmer","year":"2011","journal-title":"Bratisl Lek Listy"},{"key":"2025121220205486000_5.8.e007433.20","doi-asserted-by":"publisher","DOI":"10.1007\/s10803-005-0052-3"},{"key":"2025121220205486000_5.8.e007433.21","first-page":"1040","article-title":"The ratio of 2nd and 4th digit length in autistic children","volume":"92","author":"Noipayak","year":"2009","journal-title":"J Med Assoc Thai"},{"key":"2025121220205486000_5.8.e007433.22","doi-asserted-by":"crossref","first-page":"356","DOI":"10.1016\/j.braindev.2009.05.005","article-title":"Study of HOXD genes in autism particularly regarding the ratio of second to fourth digit length","volume":"32","author":"Sugie","year":"2010","journal-title":"Brain Dev"},{"key":"2025121220205486000_5.8.e007433.23","first-page":"94","article-title":"[Phenotypic features in autistic individuals: the finger length ratio (2D:4D), hair whorl, and hand dominance]","volume":"24","author":"Aksu","year":"2013","journal-title":"Turk Psikiyatri Derg"},{"key":"2025121220205486000_5.8.e007433.24","doi-asserted-by":"crossref","first-page":"176","DOI":"10.1002\/ajhb.22495","article-title":"2D:4D ratio in children at familial high-risk for eating disorders: the role of prenatal testosterone exposure","volume":"26","author":"Kothari","year":"2014","journal-title":"Am J Hum Biol"},{"key":"2025121220205486000_5.8.e007433.25","doi-asserted-by":"crossref","first-page":"491","DOI":"10.1002\/aur.1384","article-title":"Testing the extreme male brain theory of autism spectrum disorder in a familial design","volume":"7","author":"Hauth","year":"2014","journal-title":"Autism Res"},{"key":"2025121220205486000_5.8.e007433.26","first-page":"67","article-title":"Einige Bemerkungen \u00fcber einen schwankenden Charakter in der Hand des Menschen","volume":"8","author":"Ecker","year":"1875","journal-title":"Arch Anthropol"},{"key":"2025121220205486000_5.8.e007433.27","doi-asserted-by":"publisher","DOI":"10.1002\/ar.1090460210"},{"key":"2025121220205486000_5.8.e007433.28","doi-asserted-by":"publisher","DOI":"10.1002\/ajhb.21054"},{"key":"2025121220205486000_5.8.e007433.29","doi-asserted-by":"publisher","DOI":"10.1177\/08830738060210101601"},{"key":"2025121220205486000_5.8.e007433.30","doi-asserted-by":"publisher","DOI":"10.1002\/ajpa.1330430305"},{"key":"2025121220205486000_5.8.e007433.31","doi-asserted-by":"publisher","DOI":"10.1016\/j.psyneuen.2007.01.007"},{"key":"2025121220205486000_5.8.e007433.32","doi-asserted-by":"publisher","DOI":"10.1098\/rspb.2005.3100"},{"key":"2025121220205486000_5.8.e007433.33","doi-asserted-by":"publisher","DOI":"10.1093\/humrep\/13.11.3000"},{"key":"2025121220205486000_5.8.e007433.34","doi-asserted-by":"publisher","DOI":"10.1093\/humrep\/deg198"},{"key":"2025121220205486000_5.8.e007433.35","doi-asserted-by":"publisher","DOI":"10.1210\/en.2009-0774"},{"key":"2025121220205486000_5.8.e007433.36","doi-asserted-by":"publisher","DOI":"10.1006\/hbeh.2002.1830"},{"key":"2025121220205486000_5.8.e007433.37","doi-asserted-by":"crossref","first-page":"221","DOI":"10.1002\/aur.1230","article-title":"Digit ratio 2D:4D in relation to autism spectrum disorders, empathizing, and systemizing: a quantitative review","volume":"5","author":"Honekopp","year":"2012","journal-title":"Autism Res"},{"key":"2025121220205486000_5.8.e007433.38","doi-asserted-by":"publisher","DOI":"10.1007\/s10803-013-1819-6"},{"key":"2025121220205486000_5.8.e007433.39","doi-asserted-by":"publisher","DOI":"10.1093\/ije\/dys064"},{"key":"2025121220205486000_5.8.e007433.40","unstructured":"Avon Longitudinal Study of Parents and Children. ALSPAC: Data Dictionary. ALSPAC. 2014. Updated 21 April, 2014. http:\/\/www.bris.ac.uk\/alspac\/researchers\/data-access\/data-dictionary\/ (accessed 28 Aug 2014)."},{"key":"2025121220205486000_5.8.e007433.41","doi-asserted-by":"publisher","DOI":"10.1111\/j.1469-8749.2008.03042.x"},{"key":"2025121220205486000_5.8.e007433.42","first-page":"481","article-title":"Mental health in the United States: parental report of diagnosed autism in children aged 4\u201317 years\u2014United States, 2003\u20132004","volume":"55","author":"Center for Disease Control and Prevention (CDC)","year":"2006","journal-title":"MMWR Morb Mortal Wkly Rep"},{"key":"2025121220205486000_5.8.e007433.43","doi-asserted-by":"publisher","DOI":"10.1111\/j.1365-3016.2012.01294.x"},{"key":"2025121220205486000_5.8.e007433.44","doi-asserted-by":"publisher","DOI":"10.1007\/s10803-013-1849-0"},{"key":"2025121220205486000_5.8.e007433.45","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0012633"},{"key":"2025121220205486000_5.8.e007433.46","doi-asserted-by":"publisher","DOI":"10.1017\/S0021963098002832"},{"key":"2025121220205486000_5.8.e007433.47","doi-asserted-by":"publisher","DOI":"10.1038\/42706"},{"key":"2025121220205486000_5.8.e007433.48","unstructured":"Rutter M , Tizard J , Whitmore K . Education, health & behaviour. London, UK: Longman, 1970."},{"key":"2025121220205486000_5.8.e007433.49","unstructured":"Buss A , Plomin R . Temperament: early developing personality traits. Hillsdale, NJ: Lawrence Erlbaum, 1984."},{"key":"2025121220205486000_5.8.e007433.50","doi-asserted-by":"publisher","DOI":"10.1016\/j.ajhg.2010.02.017"},{"key":"2025121220205486000_5.8.e007433.51","unstructured":"Office of Population Censuses and Surveys. Standard Occupational Classification, Vol 3. London, UK: Her Majesty's Stationery Office, 1991."},{"key":"2025121220205486000_5.8.e007433.52","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0011551"},{"key":"2025121220205486000_5.8.e007433.53","doi-asserted-by":"publisher","DOI":"10.1016\/j.jaac.2012.02.012"},{"key":"2025121220205486000_5.8.e007433.54","doi-asserted-by":"crossref","first-page":"767","DOI":"10.1016\/j.paid.2010.01.030","article-title":"Is digit ratio (2D:4D) related to systemizing and empathizing? Evidence from direct finger measurements reported in the BBC internet survey","volume":"48","author":"Manning","year":"2010","journal-title":"Pers Individ Diff"},{"key":"2025121220205486000_5.8.e007433.55","doi-asserted-by":"publisher","DOI":"10.1016\/S1090-5138(00)00052-0"},{"key":"2025121220205486000_5.8.e007433.56","doi-asserted-by":"publisher","DOI":"10.1016\/j.earlhumdev.2003.12.002"},{"key":"2025121220205486000_5.8.e007433.57","doi-asserted-by":"publisher","DOI":"10.1016\/j.yhbeh.2008.10.010"},{"key":"2025121220205486000_5.8.e007433.58","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.1108312108"},{"key":"2025121220205486000_5.8.e007433.59","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0042372"},{"key":"2025121220205486000_5.8.e007433.60","doi-asserted-by":"publisher","DOI":"10.1016\/j.physbeh.2009.11.015"},{"key":"2025121220205486000_5.8.e007433.61","doi-asserted-by":"crossref","first-page":"185","DOI":"10.3389\/fendo.2013.00185","article-title":"No evidence that 2D:4D is related to the number of CAG repeats in the androgen receptor gene","volume":"4","author":"Honekopp","year":"2013","journal-title":"Front Endocrinol (Lausanne)"},{"key":"2025121220205486000_5.8.e007433.62","doi-asserted-by":"publisher","DOI":"10.1016\/S1090-5138(03)00052-7"},{"key":"2025121220205486000_5.8.e007433.63","doi-asserted-by":"publisher","DOI":"10.1007\/s10519-010-9404-7"},{"key":"2025121220205486000_5.8.e007433.64","doi-asserted-by":"publisher","DOI":"10.1038\/ng.385"},{"key":"2025121220205486000_5.8.e007433.65","doi-asserted-by":"publisher","DOI":"10.1002\/ajhb.20763"}],"container-title":["BMJ Open"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/syndication.highwire.org\/content\/doi\/10.1136\/bmjopen-2014-007433","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,12,13]],"date-time":"2025-12-13T04:21:05Z","timestamp":1765599665000},"score":1,"resource":{"primary":{"URL":"https:\/\/bmjopen.bmj.com\/lookup\/doi\/10.1136\/bmjopen-2014-007433"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2015,8]]},"references-count":65,"journal-issue":{"issue":"8","published-online":{"date-parts":[[2015,8,25]]},"published-print":{"date-parts":[[2015,8]]}},"alternative-id":["10.1136\/bmjopen-2014-007433"],"URL":"https:\/\/doi.org\/10.1136\/bmjopen-2014-007433","relation":{},"ISSN":["2044-6055","2044-6055"],"issn-type":[{"value":"2044-6055","type":"print"},{"value":"2044-6055","type":"electronic"}],"subject":[],"published":{"date-parts":[[2015,8]]}}}