{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,2]],"date-time":"2026-06-02T03:45:04Z","timestamp":1780371904382,"version":"3.54.1"},"reference-count":82,"publisher":"SAGE Publications","issue":"9","license":[{"start":{"date-parts":[[2006,8,1]],"date-time":"2006-08-01T00:00:00Z","timestamp":1154390400000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.sagepub.com\/page\/policies\/text-and-data-mining-license"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Can J Psychiatry"],"published-print":{"date-parts":[[2006,8]]},"abstract":"<jats:sec>\n                    <jats:title>Objective:<\/jats:title>\n                    <jats:p>To explore the implications for mental health services, for health education about the risks of cannabis use, and for public policy toward cannabis use of observational evidence that cannabis use is a contributory cause of psychosis.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Method:<\/jats:title>\n                    <jats:p>Using comparative analyses of similar evidence for the harmful effects of alcohol, tobacco, and amphetamine use, we considered the relation between observational evidence and action on cannabis. We examined arguments on the grounds of public health prudence for discouraging cannabis use by young individuals. With the assumption that the relation may be causal, we considered recommendations for policy in mental health services, health education, and public policy toward cannabis.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results:<\/jats:title>\n                    <jats:p>The observational evidence and biological plausibility of the hypothesis that cannabis is a contributory cause of psychosis is at least as strong as evidence for causal relations between heavy alcohol and amphetamine use and psychosis. On public health grounds, there is a good case for discouraging cannabis use among adolescents and young adults. It remains uncertain how best to discourage use and at whom campaigns to reduce cannabis use should be targeted.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions:<\/jats:title>\n                    <jats:p>We should discourage young adults seeking treatment in mental health services from using cannabis and inform them of the probable mental health risks of cannabis use, especially of early and frequent use. We must exercise caution in liberalizing cannabis laws in ways that may increase young individuals' access to cannabis, decrease their age of first use, or increase their frequency of cannabis use. We should consider the feasibility of reducing the availability of high-potency cannabis products.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1177\/070674370605100904","type":"journal-article","created":{"date-parts":[[2017,1,5]],"date-time":"2017-01-05T15:44:24Z","timestamp":1483631064000},"page":"566-574","source":"Crossref","is-referenced-by-count":32,"title":["What are the Policy Implications of the Evidence on Cannabis and Psychosis?"],"prefix":"10.1177","volume":"51","author":[{"given":"Wayne","family":"Hall","sequence":"first","affiliation":[{"name":"Professor, School of Population Health, University of Queensland, Queensland, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Louisa","family":"Degenhardt","sequence":"additional","affiliation":[{"name":"Senior Lecturer, National Drug and Alcohol Research Centre, University of New South Wales, Sydney, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"179","published-online":{"date-parts":[[2006,8,1]]},"reference":[{"key":"bibr1-070674370605100904","first-page":"RA355","volume":"12","author":"De Irala K","year":"2005","journal-title":"Med Sci Monit"},{"key":"bibr2-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1016\/S0140-6736(04)16235-1"},{"key":"bibr3-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1111\/j.1360-0443.2005.01117.x"},{"key":"bibr4-070674370605100904","volume-title":"Marijuana myths, marijuana facts. A review of the scientific evidence","author":"Zimmer L","year":"1997"},{"key":"bibr5-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1177\/070674370605100903"},{"key":"bibr6-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1192\/bjp.184.2.110"},{"key":"bibr7-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1136\/bmj.332.7534.172"},{"key":"bibr8-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1177\/0269881105049040"},{"key":"bibr9-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1016\/S0140-6736(04)16200-4"},{"key":"bibr10-070674370605100904","doi-asserted-by":"publisher","DOI":"10.31887\/DCNS.2005.7.1\/mweiser"},{"key":"bibr11-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1017\/S0033291702006402"},{"key":"bibr12-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1111\/j.1360-0443.2005.01001.x"},{"key":"bibr13-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1136\/bmj.38267.664086.63"},{"key":"bibr14-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1093\/aje\/kwf043"},{"key":"bibr15-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1136\/bmj.325.7374.1199"},{"key":"bibr16-070674370605100904","volume-title":"Quasi-Experimentation: Design and Analysis Issues for Field Settings","author":"Cook TD","year":"1979"},{"key":"bibr17-070674370605100904","volume-title":"The health and psychological consequences of cannabis use","author":"Hall W","year":"2001"},{"key":"bibr18-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1054\/mehy.2000.1261"},{"key":"bibr19-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1016\/S0278-5846(01)00162-2"},{"key":"bibr20-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1016\/S0920-9964(00)00132-8"},{"key":"bibr21-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1017\/CBO9780511543630.012"},{"key":"bibr22-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1016\/j.biopsych.2005.01.026"},{"key":"bibr23-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1080\/09595230412331324554"},{"key":"bibr24-070674370605100904","first-page":"283","volume-title":"Textbook of psychiatric epidemiology","author":"Bromet EJ","year":"1995"},{"key":"bibr25-070674370605100904","volume-title":"Schizophrenia genesis: The origins of madness","author":"Gottesman","year":"1991"},{"key":"bibr26-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1136\/bmj.325.7374.1212"},{"key":"bibr27-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1016\/0920-9964(94)00053-B"},{"key":"bibr28-070674370605100904","first-page":"180S","volume":"17","author":"Verdoux H","year":"2002","journal-title":"Eur Psychiatry"},{"key":"bibr29-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1016\/0140-6736(90)90745-Q"},{"key":"bibr30-070674370605100904","unstructured":"Donnelly N, Hall WD. Patterns of cannabis use in Australia. Canberra (AU): Australian Government Publishing Service; 1994. p 106."},{"key":"bibr31-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1192\/bjp.187.6.510"},{"key":"bibr32-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1192\/bjp.bp.104.007237"},{"key":"bibr33-070674370605100904","first-page":"1","volume-title":"The health effects of cannabis","author":"Hall W.","year":"1999"},{"key":"bibr34-070674370605100904","doi-asserted-by":"publisher","DOI":"10.2105\/AJPH.91.2.196"},{"key":"bibr35-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1093\/jhmas\/jrh088"},{"key":"bibr36-070674370605100904","volume-title":"Smoking and Health","author":"Royal College of Physicians","year":"1962"},{"key":"bibr37-070674370605100904","volume-title":"Smoking and Health","author":"US Surgeon General","year":"1964"},{"key":"bibr38-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1007\/s11920-001-0027-9"},{"key":"bibr39-070674370605100904","doi-asserted-by":"publisher","DOI":"10.15288\/qjsa.1955.16.001"},{"key":"bibr40-070674370605100904","volume-title":"Organic psychiatry: The psychological consequences of cerebral disorder","author":"Lishman WA","year":"1987","edition":"2"},{"key":"bibr41-070674370605100904","volume-title":"Amphetamine psychosis. Maudsley monograph number 5","author":"Connell PH","year":"1958"},{"key":"bibr42-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1001\/archpsyc.1973.04200010020003"},{"key":"bibr43-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1016\/0022-3956(74)90064-8"},{"key":"bibr44-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1192\/bjp.185.3.196"},{"key":"bibr45-070674370605100904","volume-title":"Psychostimulant use in Australia","author":"Hall W","year":"1993"},{"key":"bibr46-070674370605100904","unstructured":"Degenhardt L, Roxburgh A, McKetin R. Hospital stays for drug related psychotic episodes in Australia, 1993\u20132004. Med J Aust. Forthcoming."},{"key":"bibr47-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1017\/S0033291701003865"},{"key":"bibr48-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1038\/sj.npp.1300996"},{"key":"bibr49-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1001\/jama.1995.03520340039033"},{"key":"bibr50-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1192\/bjp.187.4.306"},{"key":"bibr51-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1001\/archpsyc.1994.03950040017002"},{"key":"bibr52-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1016\/j.eurpsy.2004.09.013"},{"key":"bibr53-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1017\/CBO9780511544248"},{"key":"bibr54-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1002\/j.1552-4604.2002.tb06000.x"},{"key":"bibr55-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1017\/S0813483900004356"},{"key":"bibr56-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1037\/0022-006X.60.6.845"},{"key":"bibr57-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1097\/00005053-199302000-00003"},{"key":"bibr58-070674370605100904","volume-title":"Psychosocial treatment programmes for people with both severe mental illness and substance misuse (Cochrane Review). The Cochrane Library: Volume 1","author":"Jeffery DP","year":"2004"},{"key":"bibr59-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1097\/00005053-199509000-00002"},{"key":"bibr60-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1254\/jphs.FMJ04003X4"},{"key":"bibr61-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pmed.0030039"},{"key":"bibr62-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1136\/bmj.325.7374.1195"},{"key":"bibr63-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1080\/09595230410001645574"},{"key":"bibr64-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1046\/j.1360-0443.1998.931014754.x"},{"key":"bibr65-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1177\/0143034399201008"},{"key":"bibr66-070674370605100904","doi-asserted-by":"publisher","DOI":"10.3109\/09687639509035750"},{"key":"bibr67-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1177\/002204269602600210"},{"key":"bibr68-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1080\/09595239600185791"},{"key":"bibr69-070674370605100904","first-page":"87","volume-title":"Preventing harmful substance use: The evidence base for policy and practice","author":"Toumbourou J","year":"2004"},{"key":"bibr70-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1146\/annurev.publhealth.26.021304.144610"},{"key":"bibr71-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1093\/her\/cyf050"},{"key":"bibr72-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pmed.0020141"},{"key":"bibr73-070674370605100904","unstructured":"Cresswell A, Kearney S. Weak drug laws linked to madness. The Australian 2005 October 29;Sect 1: All-round Country (p 1)."},{"key":"bibr74-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1111\/j.1360-0443.1997.tb03668.x"},{"key":"bibr75-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1017\/CBO9780511470219"},{"key":"bibr76-070674370605100904","volume-title":"Effects of the Cannabis Expiation Notice Scheme on levels and patterns of cannabis use in South Australia: Evidence from the National Drug Strategy Household Surveys 1985\u20131995","author":"Donnelly N","year":"1999"},{"key":"bibr77-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1002\/hec.796"},{"key":"bibr78-070674370605100904","doi-asserted-by":"publisher","DOI":"10.2307\/3342518"},{"key":"bibr79-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1017\/CBO9780511754272"},{"key":"bibr80-070674370605100904","volume-title":"Statistics on drug use in Australia 2004","author":"Australian Institute of Health and Welfare","year":"2005"},{"key":"bibr81-070674370605100904","doi-asserted-by":"publisher","DOI":"10.1111\/j.1467-842X.2000.tb00500.x"},{"key":"bibr82-070674370605100904","volume-title":"The Cigarette Papers","author":"Glantz SA","year":"1996"}],"container-title":["The Canadian Journal of Psychiatry"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.1177\/070674370605100904","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.1177\/070674370605100904","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,4,28]],"date-time":"2026-04-28T16:10:16Z","timestamp":1777392616000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.sagepub.com\/doi\/10.1177\/070674370605100904"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2006,8]]},"references-count":82,"journal-issue":{"issue":"9","published-print":{"date-parts":[[2006,8]]}},"alternative-id":["10.1177\/070674370605100904"],"URL":"https:\/\/doi.org\/10.1177\/070674370605100904","relation":{},"ISSN":["0706-7437","1497-0015"],"issn-type":[{"value":"0706-7437","type":"print"},{"value":"1497-0015","type":"electronic"}],"subject":[],"published":{"date-parts":[[2006,8]]}}}