Economic Evaluation Ken Stein Public Health Physician North & East Devon Health Authority University of Exeter

Questions Can it work? Efficacy Does it work? Effectiveness Should it be used, given other calls on a fixed budget? Economics Is it reaching those whom it should? Availability EBM Policy Audit Development

A national problem Higgenbottoms syndrome is now recognised as a national problem There are grave concerns about a lottery of postcode dancing NICE takes action... Your PCT is not convinced and asks you to review the evidence You need some background to deal with the results of your search and the NICE evaluation

Economic analysis involves Identification of alternatives … their consequences … and their costs … the values of these … and how they compare … to inform the decision on whether you should do it

Spotting economic analyses Is there a comparison of two or more alternatives? Are both costs and consequences examined? If not - the study is not an economic evaluation but may be: description of costs or outcomes evaluation of efficacy or effectivenes cost analysis

CHOICE Treatment A Treatment B Consequences PERSPECTIVE...

Types of economic analysis Cost minimisation Cost effectiveness Cost utility Cost benefit

Defining economic analyses

Cost effectiveness How much it costs to get an effect e.g. how much per fight prevented by ballet therapy? i.e the RATIO of COSTS to EFFECTS How might different cost effectiveness ratios for alternative treatments appear? The cost effectiveness plane

Alternative less effective and more costly E Alternative cheaper but less effective D Alternative more effective and less costly C E.g. £20,000 per QALY COST OUTCOME A B Alternative more effective but more costly

Marginal (syn: incremental) or average analysis? An analysis of different doses of a cholesterol lowering drug shows that 80mg per day gives a cost effectiveness of £25,000 per life year gained (LYG) 40mg per day gives £15,000 per LYG So its probably worth giving 80mg where possible as the extra LYG costs only £10,000? Well...

COST LYG £25,000/LYG £15,000/LYG £85,000/LYG 80mg 40mg

Marginal cost effectiveness = whats the extra cost to get the extra effectiveness? i.e. Difference in costs Difference in effectiveness

Quality Adjusted Life Years A 1985, good quality, 10 year cohort study of HS showed: Life expectancy is reduced by one year compared to national life tables HS sufferers spent, on average: 120 person days per year with: –limited mobility –episodic incontinence –moderate pain –depression of mood

QALY burden of HS 100 people with HS will, over 10 years: lose 100 life years lose 100 x 0.3 years of full quality of life

Utilities and QALYs Utility is a measure of preference about an outcome (a health state), giving an indication of the relative value placed on the health state Scaled 0 (death) to 1 (full health) Utilities are used to weight time according to quality of life spent during that time A health state with a utility of 0.5 lasting two years is equivalent to one year in full health Allows us to consider differences in treatments which involve changes in quality as well as quantity of life

QALY gains - example QALYs - patient 1 QALYs - patient 2 QALYs gained Death LYG gained

Utitilies and HS Description of HS health states to experts for opinion (Dr Phillips says utlity = 0.95 ) Eliciting utilities with HS sufferers –Visual analogue scale –Time trade off (utility = 0.67) –Standard Gamble Mapping onto health state measures for which preferences are known e.g. EQ5D –Mobility –Self-care –Usual activity (utility = 0.85) –Pain / discomfort –Anxiety / depression PS - these are the real values for utilities associated with impotence used in an evaluation of the cost utility of viagra

The NICE appraisal Was a well defined question posed? TITLE: Cost effectiveness and Cost Utility of Ballet Therapy for Higginbottoms Syndrome - a report to NICE, January 2001 Perspective was the NHS, with potential impacts on non-health sector identified but not included in the analysis

Was a comprehensive description of competing alternatives given? Intervention: Fonteyns model for ballet therapy Comparator: do nothing

Was the analysis based on valid evidence? Fonteyn M et al five year RCT of Ballet therapy for HS Number of fights prevented = 13 per year

Were all important and relevant resources identified for each alternative? Costs Ballet therapy - GP, specialist community dancing support team, capital for ballet schools, trainer costs, follow up, replacement dresses. Identified from micro-costing study Savings Healthcare costs associated with HS, estimated from National reference costs for HRGs Outcomes Number of fights QALYs based on healthstates associated with fights and treatment, valued by expert opinion

Results Ballet therapy costs an average of £14,756 per year Savings to the NHS: £4,875 per year Total costs to the NHS of implementing ballet therapy would be £483m over 5 years Incremental benefits would be: 13 fights prevented 0.24 QALYs gained

Results COST OUTCOME Cost per fight averted = £744

Results COST OUTCOME Cost per QALY = £41,230 £20,000 per QALY

Were healthcare use and health outcome consequences adjusted for the different times at which they occurred? Undiscounted Year 1 costs = 1,000 Year 2 costs = 1,000 Year 3 costs = 1,000 Year 4 costs = 1,000 Year 5 costs = 1,000 6% Year 1 = £1000 Year 2 = £943 Year 3 = £890 Year 4 = £840 Year 5 = £792 TOTAL = £4,465

Was an adequate sensitivity analysis performed? One way sensitivity analysis on costs and outcomes (number of fights, utilities associated with health states) showed results reasonably stable Cost effectiveness: £530 to £2400 / FP Cost utility: £35,000 to £56,000 per QALY (over 5 years - no modelling beyond the end of the trial undertaken) Dress and ballet trainer costs were most influential in the sensitivity analysis

Will the results help you? Were the conclusions justified? Can the results be applied to your population? Effectiveness of ballet therapy? Implementation costs different (shortage or excess of ballet trainers, availability of dresses, dispersed population)? Costs of healthcare (savings) different? Organisation of the healthcare system? Discounting rate may differ?

Appraisal decision Ballet therapy is an effective treatment but benefits are modest compared to other calls on the NHS budget. Considerable uncertainty remains over the long term effects of ballet therapy and further research is required, incorporating an economic analysis from a broader societal perspective… The International Confederation of Ballet Trainers has contested this decision