Table 5 Assessments of the quality of the studies with the Drummond checklist and the CHEC list
British Medical Journal Checklist | 1a | 2a | 3a | 4a | 5a | 6a | 7a | 8a | 9a | 10a | 11a |
|---|---|---|---|---|---|---|---|---|---|---|---|
 1. The research question is stated. | - | - | ✓ | ✓ | ✓ | ✓ | ✓ | - | ✓ | ✓ | ✓ |
 2. The economic importance of the research question is stated. | ✓ | - | ✓ | ✓ | - | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
 3. The viewpoint(s) of the analysis are clearly stated and justified. | - | ✓ | - | ✓ | - | - | ✓ | ✓ | - | - | - |
 4. The rationale for choosing alternative programmes or interventions compared is stated. | ✓ | - | - | - | - | - | ✓ | - | ✓ | - | - |
 5. The alternatives being compared are clearly described | ✓ | ✓ | ✓ | ✓ | - | - | - | - | ✓ | ✓ | ✓ |
 6. The form of economic evaluation used is stated. | - | ✓ | ✓ | ✓ | - | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
 7. The choice of form of economic evaluation is justified in relation to the questions addressed. | NC | ✓ | ✓ | ✓ | - | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
 8. The source(s) of effectiveness estimates used are stated. | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
 9. Details of the design and results of effectiveness study are given (if based on a single study). | ✓ | NA | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | - | ✓ | ✓ |
 10. Details of the methods of synthesis or meta-analysis of estimates are given (if based on a synthesis of a number of effectiveness studies). | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA |
 11. The primary outcome measure(s) for the economic evaluation are clearly stated. | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
 12. Methods to value benefits are stated. | ✓ | ✓ | NA | ✓ | ✓ | NA | ✓ | NA | ✓ | ✓ | ✓ |
 13. Details of the subjects from whom valuations were obtained were given. | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
 14. Productivity changes (if included) are reported separately. | NA | ✓ | NA | NA | NA | NA | NA | NA | NA | - | - |
 15. The relevance of productivity changes to the study question is discussed. | - | - | - | - | - | - | ✓ | - | - | - | - |
 16. Quantities of resource use are reported separately from their unit costs. | ✓ | ✓ | - | - | - | - | - | - | ✓ | ✓ | ✓ |
 17. Methods for the estimation of quantities and unit costs are described. | - | - | - | - | ✓ | - | ✓ | ✓ | ✓ | ✓ | ✓ |
 18. Currency and price data are recorded. | ✓ | ✓ | - | ✓ | - | - | - | ✓ | ✓ | ✓ | ✓ |
 19. Details of currency of price adjustments for inflation or currency conversion are given. | ✓ | ✓ | - | - | - | - | ✓ | - | ✓ | ✓ | ✓ |
 20. Details of any model used are given | NA | ✓ | ✓ | ✓ | ✓ | ✓ | NA | NA | ✓ | NA | NA |
 21. The choice of model used and the key parameters on which it is based are justified. | NA | - | - | ✓ | - | - | NA | NA | - | NA | NA |
 22. Time horizon of costs and benefits is stated. | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
 23. The discount rate(s) is stated. | NA | NA | NA | NA | NA | NA | ✓ | NA | ✓ | ✓ | ✓ |
 24. The choice of discount rate(s) is justified. | NA | NA | NA | NA | NA | NA | ✓ | NA | ✓ | ✓ | ✓ |
 25. An explanation is given if costs and benefits are not discounted. | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA |
 26. Details of statistical tests and confidence intervals are given for stochastic data. | - | - | ✓ | - | ✓ | - | ✓ | ✓ | ✓ | - | - |
 27. The approach to sensitivity analysis is given. | ✓ | - | ✓ | - | - | - | ✓ | NC | ✓ | ✓ | ✓ |
 28. The choice of variables for sensitivity analysis is justified. | ✓ | NA | NA | NA | NA | NA | ✓ | NA | ✓ | ✓ | ✓ |
 29. The ranges over which the variables are varied are justified. | NC | NA | NA | NA | NA | NA | ✓ | NA | ✓ | ✓ | ✓ |
 30. Relevant alternatives are compared. | ✓ | NC | - | NC | ✓ | NS | ✓ | ✓ | ✓ | ✓ | ✓ |
 31. Incremental analysis is reported. | ✓ | ✓ | - | ✓ | ✓ | - | ✓ | - | ✓ | ✓ | ✓ |
 32. Major outcomes are presented in a disaggregated as well as aggregated form | ✓ | ✓ | ✓ | - | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
 33. The answer to the study question is given. | ✓ | NC | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
 34. Conclusions follow from the data reported. | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | - | - |
 35. Conclusions are accompanied by the appropriate caveats. | - | - | ✓ | ✓ | - | ✓ | ✓ | ✓ | - | ✓ | - |
Total score British medical journal checklist | 68 % | 61 % | 63 % | 68 % | 54 % | 52 % | 86 % | 70 % | 83 % | 81 % | 77 % |
CHEC list | |||||||||||
 1. Is the study population clearly described? | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
 2. Are competing alternatives clearly described? | ✓ | ✓ | ✓ | ✓ | - | - | - | - | ✓ | ✓ | ✓ |
 3. Is a well-defined research question posed in answerable form? | - | - | ✓ | ✓ | ✓ | ✓ | ✓ | - | ✓ | ✓ | ✓ |
 4. Is the economic study design appropriate to the stated objective? | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
 5. Is the chosen time horizon appropriate to include relevant costs and consequences? | NS | NS | ✓ | NS | NS | NS | ✓ | NS | NS | ✓ | ✓ |
 6. Is the actual perspective chosen appropriate? | - | ✓ | - | - | - | - | ✓ | - | - | - | - |
 7. Are all important and relevant costs for each alternative identified? | - | - | NS | - | - | - | - | - | - | ✓ | ✓ |
 8. Are all costs measured appropriately in physical units? | ✓ | ✓ | - | - | - | - | ✓ | - | ✓ | ✓ | ✓ |
 9. Are costs valued appropriately? | ✓ | ✓ | - | ✓ | ✓ | NS | ✓ | ✓ | ✓ | ✓ | ✓ |
 10. Are all important and relevant outcomes for each alternative identified? | - | - | ✓ | ✓ | - | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
 11. Are all outcomes measured appropriately? | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
 12. Are outcomes valued appropriately? | - | ✓ | ✓ | ✓ | ✓ | ✓ | - | ✓ | ✓ | ✓ | ✓ |
 13. Is an incremental analysis of costs and outcomes of alternatives performed? | ✓ | ✓ | - | ✓ | ✓ | - | ✓ | - | ✓ | ✓ | ✓ |
 14. Are all future costs and outcomes discounted appropriately? | NA | NA | NA | NA | NA | NA | ✓ | NA | ✓ | ✓ | ✓ |
 15. Are all important variables, whose values are uncertain, appropriately subjected to sensitivity analysis? | ✓ | - | - | - | - | - | ✓ | - | ✓ | ✓ | ✓ |
 16. Do the conclusions follow from the data reported? | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | - | - |
 17. Does the study discuss the generalizability of the results to other settings and patient/client groups? | - | - | ✓ | - | - | ✓ | ✓ | ✓ | - | - | - |
 18. Does the article indicate that there is no potential conflict of interest of study researcher(s) and funder(s)? | - | ✓ | - | - | - | - | - | - | - | - | - |
 19. Are ethical and distributional issues discussed appropriately? | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
Total score CHECb | 56 % | 67 % | 61 % | 61 % | 50 % | 50 % | 79 % | 50 % | 79 % | 74 % | 74 % |