1. 1 Cost-effectiveness analysis : concepts and example from the FIOCRUZ- INSERM programme related to screening strategies of TB in jails of Rio 03/08/2006 Dr Michaël Schwarzinger, MD, MPH Inserm 707, Paris Direction des Etudes Médico-Economiques, Institut de Cancérologie Gustave Roussy, Villejuif

2. 2 Why am I here? Background: A French physician Found of evidence-based medicine Interested in preferences of patients (and more broadly society) With some background in modeling and economic issues. Current work: Financing of the Institut de Cancérologie Gustave Roussy Research in health economics Purpose of my visit in Rio: Provide support for the CEA of screening strategies of TB in jails of RIo ‘Do caos inicial à explosao da vida’… (Beija-Flor 2006)

3. 3 What is cost-effectiveness analysis? ‘CEA is an aid to decision making (among competing alternatives in situation of limited resources), not a complete procedure for making decisions, because it cannot incorporate all the values relevant to the decisions’ (Gold et al. 1996) A quantitative method to make (or think about) decisions in the face of uncertainty

4. 4 How to perform a CEA? 1. Ask an explicit question 2. Make a decision tree: Alternative strategies including the current reference strategy (things you do) Possible outcomes (things that happen) 3. Estimate the probability of each outcome 4. Estimate health value for each outcome: Case of TB screened… Years of life saved QALY (quality-adjusted life year) saved DALY (disability-adjusted life year) avoided 5. Estimate the costs of each strategy 6. Calculate the expected value and costs of each strategy 7. Conduct sensitivity analysis

5. 5 How to decide from a CEA? 1. Incremental cost-effectiveness ratio A measure of ‘value for money’ Ex: The new strategies X and Y will cost 100 R$ and 300 R$ per additional case of TB screened as compared to the reference (current) strategy Difference in costs Difference in health effects

6. 6 A D B C Increase in health effects More costly Less costly Decrease in health effects Y=300 X=100 X is better for money Strategy is less effective and more costly Strategy is more effective and more costly Strategy is less effective and less costly Strategy is more effective and less costly How to decide from a CEA? 2. Comparison of competing strategies

7. 7 How to decide from a CEA? 3. Comparison across interventions in ‘league tables’ Bobadilla JL et al. Bull WHO 1994;72:653-62. IMSC: Integrated management of the sick child; EPI: Expanded programme of immunization DiseaseInterventions ICER ($/DALY) % total Children Respiratory infections9815%IMSC30-100 Perinatal morbidity and mortality9615%Prenatal and delivery care30-100 Family planing20-150 Diarrhoeal disease9214%IMSC30-100 Diseases preventable through immunization 6510%EPIplus12-30 Malaria315%IMSC30-100 Protein-energy malnutrition122%IMSC30-100 Vitamine-A deficiency122%EPIplus12-30 Iodine deficiency91%Iodine supplementation19-37 Sous-total:415 63% Total660100% DALYs lost (million) Where is X as compared to other funded interventions in Brazil???

8. 8 Antibiotherapy + Influenza infection + Zanamivir +RFT + Bedside Rapid Flu Test (RFT) with zanamivir prescription Zanamivir - A A RFT - Influenza infection - Antibiotherapy + Antibiotherapy - Systematic zanamivir prescription No zanamivir A Consultation within 2 days of the onset of influenza- like symptoms among healthy working adults A A = Bedside rapid flu test and zanamivir prescription in healthy working adults: a cost-benefit analysis (Schwarzinger et al. Pharmacoeconomics 2003)

9. 9

10. 10 Bedside rapid flu test and zanamivir prescription in healthy working adults: a cost-benefit analysis (Schwarzinger et al. Pharmacoeconomics 2003)

11. 11 Bedside rapid flu test and zanamivir prescription in healthy working adults: a cost-benefit analysis (Schwarzinger et al. Pharmacoeconomics 2003)

12. 12 Bedside rapid flu test and zanamivir prescription in healthy working adults: a cost-benefit analysis (Schwarzinger et al. Pharmacoeconomics 2003)

13. 13 Economic evaluations of neuraminidase inhibitors in adults (Schwarzinger et al. Expert Rev. Pharmacoeconomics Outcomes Res. 2003)

14. 14 Economic evaluations of neuraminidase inhibitors in adults (Schwarzinger et al. Expert Rev. Pharmacoeconomics Outcomes Res. 2003)

15. 15 Cross-national agreement on disability weights (Schwarzinger et al. Population Health Metrics 2003)

16. 16 Major impacts on CEA results 1. Incremental analysis: The relevant analysis concerns the marginal change, not the total activity. 2. Choice of reference strategy: Existing practice (‘status quo’) Best-available strategy Viable low-cost strategy 3. Choice of outcome measure Various methods, various (sub-)populations, various results… QALY/DALY are recommended 4. Decision across interventions needs an explicit dollar threshold for ICER: Country-specific 34% of 228 CEA articles did mention it, with a median of 50,000$/QALY (Neumann et al. Health Affairs 2000)

17. 17 Limits in the use of CEA 1. Lack of understanding: ‘clinicians feel left out or put down by people conducting CEA… they can’t check the calculations to make sure it is being done right’ (Eddy 1992) 2. Mistrust of methods Methodological discrepancies/absence of standards Lack of relevance: CEA does not explore budget impacts 3. Mistrust of motives of the investigators and their sponsors 4. Legal and regulatory constraints 5. Political factors: ‘rationing’ is not popular 6. Ethical objections: CEA paradigm: maximise overall health benefits => distributional neutrality People may want to achieve other goals in setting priorities (e.g. people most in need, children…)

18. 18 CEA of screening strategies of TB in jails of Rio de Janeiro (FIOCRUZ-Inserm) Prevalence of TB: 4.6% Possible strategies:

19. Susc E (fast) TnTi L (slow) DnDi Yi Trt fail. Rec. 21 3 16 56 4 7 14 15 1011 28 29 2223 Yn Trt fail. 12 13 8 9 18 17 19 30 31 32 33 2021 An epi model of the natural history of TB including possible screening impacts

20. 20 Parameters of the epi model

21. 21 Perspective Refinements: Modeling for all jails of Rio DALYs of a TB case screened and treated Estimates of unit costs: economic opportunity costs (lab, X-ray machine belong to the jails) rather than financial costs Sensitivity analysis Budget impact