Health Care Management Science

, Volume 10, Issue 2, pp 151–162 | Cite as

Dynamic compartmental model of trends in Australian drug use

  • Jonathan P. CaulkinsEmail author
  • Paul Dietze
  • Alison Ritter


A five-state compartment model of trends in illicit drug use in Australia is parameterized using data from multiple sources. The model reproduces historical prevalence and supports what-if analyses under the assumption that past trajectories of drug escalation and desistance persist. For fixed initiation, the system has a unique stable equilibrium. The chief qualitative finding is that even though some users escalate rapidly, regular injection drug use still adjusts to changes in incidence with considerable inertia and delay. This has important policy implications, e.g., concerning the timing of reductions in drug-related social cost generated by interventions that reduce the social cost per injection user versus those that cut drug initiation.


Dynamic modeling Drugs Epidemic Injection drug use Compartmental models 


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  1. 1.
    Model KE (1993) The effect of marijuana decriminalization on hospital emergency room drug episodes 1975–1978. J Am Stat Assoc 88:737–747CrossRefGoogle Scholar
  2. 2.
    Pacula R, Chriqui J, King J (2003) Decriminalization in the United States: what does it mean? National Bureau of Economic Research Working Paper No. 9690. NBER, Cambridge, MAGoogle Scholar
  3. 3.
    Grossman M (2004) Individual behaviors and substance use: the role of price. National Bureau of Economic Research Working Paper No. 10948. NBER, Cambridge, MAGoogle Scholar
  4. 4.
    Kandel DB (2002) Stages and pathways of drug involvement: examining the gateway hypothesis. Cambridge University Press, New YorkGoogle Scholar
  5. 5.
    Rossi C (2001) A mover-stayer type model for epidemics of problematic drug use. Bull Narc 53:39–64Google Scholar
  6. 6.
    Levin G, Roberts EB, Hirsch GB (1975) The persistent poppy: a computer-aided search for heroin policy. Ballinger, Cambridge, MAGoogle Scholar
  7. 7.
    Homer JB (1993) Projecting the impact of law enforcement on cocaine prevalence. J Drug Issues 23:281–295Google Scholar
  8. 8.
    Homer JB (1993) A system dynamics model for cocaine prevalence estimation and trend projection. J Drug Issues 23:251–279Google Scholar
  9. 9.
    Everingham SS, Rydell CP (1994) Modeling the demand for cocaine. MR-332-ONDCP/A/DPRC. RAND, Santa MonicaGoogle Scholar
  10. 10.
    Everingham SS, Rydell P, Caulkins JP (1995) Cocaine consumption in the US: estimating past trends and future scenarios. Socio-Econ Plann Sci 29:305–314CrossRefGoogle Scholar
  11. 11.
    Caulkins JP, Behrens DA, Knoll C, Tragler G, Zuba D (2004) Markov chain modeling of initiation and demand: the case of the U.S. cocaine epidemic. Health Care Manage Sci 7:319–329CrossRefGoogle Scholar
  12. 12.
    Mendez D, Warner KE, Courant PN (1998) Has smoking cessation ceased? Expected trends in the prevalence of smoking in the United States. Am J Epidemiol 148:249–258Google Scholar
  13. 13.
    Mendez D, Warner KE (2000) Smoking prevalence in 2010: why the healthy people goal is unattainable. Am J Public Health 90:401–403Google Scholar
  14. 14.
    Tengs TO, Osgood ND, Chen LL (2001) The cost-effectiveness of intensive national school-based anti-tobacco education: results from the tobacco policy model. Prev Med 33:558–570CrossRefGoogle Scholar
  15. 15.
    Tengs TO, Ahmad S, Moore R, Gage E (2004) Federal policy mandating safer cigarettes: a hypothetical simulation of the anticipated population health gains or losses. J Policy Anal and Manag 23:857–872CrossRefGoogle Scholar
  16. 16.
    Levy DT, Chaloupka F, Gitchell J, Mendez D, Warner KE (2002) The use of simulation models for the surveillance, justification and understanding of tobacco control policies. Health Care Manage Sci 5:113–120CrossRefGoogle Scholar
  17. 17.
    Dietze P, Fitzgerald J (2002) Interpreting changes in heroin supply in Melbourne: droughts, gluts or cycles? Drug Alcohol Rev 21:295–303CrossRefGoogle Scholar
  18. 18.
    Degenhardt L, Reuter P, Collins L, Hall W (2005) Evaluating explanations of the Australian ‘heroin shortage.’ Addiction 100:459–469CrossRefGoogle Scholar
  19. 19.
    Weatherburn D, Jones C, Freeman K, Makkai T (2003) Supply control and harm reduction: lessons from the Australian heroin ‘drought.’ Addiction 98:83–91CrossRefGoogle Scholar
  20. 20.
    Levy DT, Friend K (2002) Examining the effects of tobacco treatment policies on smoking rates and smoking related deaths using the SimSmoke computer simulation model. Tob Control 11:47–54CrossRefGoogle Scholar
  21. 21.
    Rydell CP, Caulkins JP, Everingham SS (1996) Enforcement or treatment: modeling the relative efficacy of alternatives for controlling cocaine. Oper Res 44:687–695Google Scholar
  22. 22.
    Behrens DA, Caulkins JP, Tragler G, Feichtinger G (2002) Why present-oriented societies undergo cycles of drug epidemics. J Econ Dyn Control 26:919–936CrossRefGoogle Scholar
  23. 23.
    Behrens DA, Caulkins JP, Tragler G, Feichtinger G (2000) Optimal control of drug epidemics: prevent and treat—but not at the same time? Manage Sci 46:333–347CrossRefGoogle Scholar
  24. 24.
    Ritter AJ, Bammer G, Hamilton M, Mazerolle L (in press) Effective drug policy: a new approach demonstrated in the drug policy modeling program. Drug Alcohol Rev (accepted 20/11/06)Google Scholar
  25. 25.
    Kaya CY, Tugai Y, Filar JA, Agrawal MR, Ali RL, Gowing LR, Cooke R (2004) Heroin users in Australia: population trends. Drug Alcohol Rev 23:107–116CrossRefGoogle Scholar
  26. 26.
    Day C, Degenhardt L, Hall W (2006) Changes in the initiation of heroin use after a reduction in heroin supply. Drug Alcohol Rev 25:307–313CrossRefGoogle Scholar
  27. 27.
    Australian Institute of Health and Welfare (1999) 1998 National drug strategy household survey: first results, drug statistics series. AIHW, CanberraGoogle Scholar
  28. 28.
    Law M G, Dore GJ, Bath N, Thompson S, Crofts N, Dolan K, Giles W, Gow P, Kaldor J, Loveday S, Powell E, Spencer J, Wodak A (2003) Modelling hepatitis C virus incidence, prevalence and long-term sequelae in Australia, 2001. Int J Epidemiol 32:717–724CrossRefGoogle Scholar
  29. 29.
    Australian institute of Health and Welfare (2002) 2001 National drug strategy household survey: first results. AIHW, CanberraGoogle Scholar
  30. 30.
    Dietze P, Jolley D, Fry C, Bammer G (2005) Transient changes in behaviour lead to heroin overdose: results from a case-crossover study of non-fatal overdose. Addiction 100:636–642CrossRefGoogle Scholar
  31. 31.
    Moore TJ, Caulkins JP, Ritter A, Dietze P, Monagle S, Pruden J (2005) Heroin markets in Australia: current understanding and future possibilities, DPMP monograph series (turning point alcohol and drug centre, Fitzroy)Google Scholar
  32. 32.
    Day C, Degenhardt L, Gilmour S, Hall W (2004) Effects of reduction in heroin supply on injecting drug use: analysis of data from needle and syringe programmes. Br Med J 329:428–429CrossRefGoogle Scholar
  33. 33.
    Topp L, Day C, Degenhardt L (2003) Changes in patterns of drug injection concurrent with a sustained reduction in the availability of heroin in Australia. Drug Alcohol Depend 70:275–286CrossRefGoogle Scholar
  34. 34.
    Byrne A (2000) Nine-year follow-up of 86 consecutive patients treated with methadone in general practice, Sydney, Australia. Drug Alcohol Rev 19:13–158Google Scholar
  35. 35.
    Coomber R, Sutton C (2006) How quick to heroin dependence. Drug Alcohol Rev 25:463–471CrossRefGoogle Scholar
  36. 36.
    Golub A, Johnson BD (2001) Variation in youthful risks of progression from alcohol and tobacco to marijuana and to hard drugs across generations. Am J Public Health 91:225–232CrossRefGoogle Scholar
  37. 37.
    Moore TJ (2006) The social costs of illicit drugs in Australia. Report for the Australian Federal Police (turning point alcohol and drug centre, Fitzroy)Google Scholar
  38. 38.
    Collins DJ, Lapsley HM (2002) Counting the cost: estimates of the social costs of drug abuse in Australia in 1988–1989. Australian Government Publishing Service, Canberra, AustraliaGoogle Scholar
  39. 39.
    Weatherburn D, Lind B (1995) Drug law enforcement policy and its impact on the heroin market. New South Wales Bureau of Crime Statistics and Research, SydneyGoogle Scholar
  40. 40.
    Hall W, Ross J, Lynskey M, Law M, Degenhardt L (2000) How many dependent opioid users are there in Australia? National Drug and Alcohol Research Centre Monograph No. 44. University of NSW, Sydney, pp 1541–1550Google Scholar
  41. 41.
    Moore TJ, Caulkins JP (2006) How cost-of-illness studies can be made more useful for illicit drug policy analysis. Applied Health Economics and Health Policy 5:75–85CrossRefGoogle Scholar
  42. 42.
    Behrens DA, Caulkins JP, Tragler G, Haunschmied JL, Feichtinger G (1999) A dynamic model of drug initiation: implications for treatment and drug control. Math Biosci 159:1–20CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2007

Authors and Affiliations

  • Jonathan P. Caulkins
    • 1
    • 2
    Email author
  • Paul Dietze
    • 3
    • 4
  • Alison Ritter
    • 3
    • 5
  1. 1.Carnegie Mellon University-Qatar CampusDohaQatar
  2. 2.H. John Heinz III School of Public Policy and ManagementCarnegie Mellon UniversityPittsburghUSA
  3. 3.Turning Point Alcohol and Drug CentreMelbourneAustralia
  4. 4.Monash Institute of Health Services ResearchMelbourneAustralia
  5. 5.National Drug and Alcohol Research CentreUniversity of New South WalesSydneyAustralia

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