1. Understanding the evidence base: the need to critically examine all the studies and evidence on drug related interventions as collected and analysed by the Cochrane Collaboration Marina Davoli Co-ordinating Editor Cochrane Drugs and Alcohol Review Group Lisbon, 6-8 May 2009

2. SUMMARY Why the evidence base Where is the evidence Future challenges and perspectives

3. A reminder of the responsibilities of practitioners, policy makers and researchers to the public Good intentions and plausible theories are no substitute for reliable evidence from empirical research about the effects of social and healthcare interventions Iain Chalmers, 8° CC 2000

7. Example I: SIDS …could it be achieved earlier?

8. Example 1: SIDS Jilbert, IJE 2005 Systematic review of effectiveness: RR of death by sleep position

9. Example 1: SIDS Jilbert suggests that the delay is attributable to a greater “believe” in theoretical mechanisms (cardiac, cerebral, etc) of death than in the evidence of effectiveness 10000 US 50000From 1970 to 1992 10000 US and 50000 european children could have survived if guidelines would have issued earlier Jilbert, IJE 2005

10. Example 2 Interventions intended to prevent delinquent adolescents from becoming career criminals

11. The likelihood of a prison sentence for a 17-20 year old convicted of criminal damage Powys 5.1% Surrey 5.9% Suffolk 8.1% Norfolk 8.3% Gloucestershire 9.8% Nottinghamshire21.1% South Yorkshire21.9% Northumbria25.3% Kent26.1% Hertfordshire31.6% Home Office statistics for Crown Courts in 1988, Guardian 23 Jan 90

12. International variation in sentencing policy Sentences for a 19-year old armed robber who stole £800,000 with four others in a bank raid NigeriaDeathN Zealand9 years H KongLifeIndia7 years Texas99 yearsDenmark6 years Greece20 yearsCanada5 years England14 yearsNorway2 years Scotland10 years Survey of the International Bar Association (1990): based on judges’ and legal experts’ responses to hypothetical cases

13. RCTs of ‘Scared Straight’ programmes TrialChange in criminal behaviour Michigan 196726 % increase Greater Egypt 1979 5 % increase Yarborough 1979 1 % increase Orchowsky 1981 2 % increase Vreeland 198111 % increase Finckenauer 198230 % increase Lewis 198314 % increase Petrosino et al 2000

14. Conclusions Responsible professionals in the health and social services need more than good intentions and plausible theories to guide their practice. Their prescriptions and proscriptions for others should be informed by reliable research evidence showing that they are more likely to do good than harm.

16. The Cochrane Collaboration An international network of people who conduct, update and disseminate systematic reviews of the effect of health care interventions. There are 51 Review Groups in the Cochrane Collaboration

17. Marina Davoli: Co-ordinating Editor Laura Amato: Managing Editor Simona Vecchi:Trial search Co. Zuzana Mitrova: Assistant Co. Robert Ali (Australia) Zhao Chengzheng (China) Fabrizio Faggiano (Italy) Michael Farrell (UK) David Foxcroft (UK) Walter Ling (USA) The editorial base The Editors Cochrane Review Group on Drugs and Alcohol

18. RCTs on interventions for drug addiction (n=6530) Specialized Register Drugs and Alcohol Cochrane Group. CL 2.2009

19. Cochrane Systematic reviews Are the result of a complex process : –Formulate a proper question –Comprehensive study search –Objective selection and data extraction –Critical evaluation of primary studies –Synthesis –Update

20. State of the art CLIB 3.2009 http://www.cdag.cochrane.org SubstanceN° ReviewsN° Protocols N° Titles registered Total Alcohol810323 Opiate204327 Psychostimulants92112 Other31 /4 Poly drugs42612 Prevention3/ /3 Total47*191379 *629 studies included/1824 considered for inclusion

21. Effectiveness of all interventions considered in CRs published in CLIB 3.2009

22. Beneficial or likely to be beneficial Trade off between benefits and harms Unknown effectiveness Unlikely to be beneficial Likely to be ineffective or harmful OTHER 100% PREVENTION 20% 70% 10% OPIATES 43% 17% 27% 13% POLY DRUGS 7% 20% 46% 27% PSYCHOSTIMULANTS 16,6% 83,3 ALCOHOL 27% 13% 60% N= 15 N= 8N= 25 N= 48N= 20N= 15

23. http://www.who.int/substance_ abuse/publications/opioid_dep endence_guidelines.pdf

24. CONCLUSIONS Cochrane reviews provide the “best available evidence” answering the questions they are planned to answer Cochrane reviews sometimes provide useful results to identify effective interventions They also identify a wide range of interventions unlikely to be beneficial and even likely to be ineffective or harmful Cochrane reviews also help in identifying areas where more systematic reviews are necessary and areas where more primary research is required

25. BUT….

26. THE EMCDDA AND THE EU SCIENTIFIC COMMUNITY PLAY A KEY ROLE Ask the question: –Help in prioritizing questions to be addressed by systematic reviews in order to be relevant for: Patients and their families Care givers Policy maker –Less than 1/3 of published studies considered for inclusion Support in making the evidence available and accessible Use the evidence to inform guidelines The Cochrane Collaboration is a “virtual” organisation open to all possible contributions

27. Country of origin of the studies included in the Specialized Register 68.3% 21.7% 4.4% 4.1% 0.7% 0.5% 0.3%