economic evaluation Flashcards
Why economic evaluations?
- mainly efficiency arguments: does it provide value for money to implement a certain intervention?
- resources for healthcare are scarce, so we need to make choices!
definition economic evaluation
- a systematic comparison of the costs and effects of two or more treatments –> do costs weigh up the extra benefits? –> Is intervention the best way to spend our money?
- not necessarily the cheapest, but “best value” –> it is okay to pay more if additional benefits way up additional costs
what do we need to measure in an economic evaluation?
- costs
2. effects
what is the aim in economic evaluations?
informing resource allocation decisions/ healthcare policy makers, more interested in effectiveness (than efficacy)
4 types of economic evaluations
- cost-minimization analysis
- cost-effectiveness analysis
- cost-utility analysis
- cost-benefit analysis
- -> determined by effect outcome that you look at
cost-minimization analysis
- we assume that effects equal (but also clinical relevant equally?)
- identification of intervention with lowest costs
- strictly speaking not a full economic evaluation: because we don’t look at outcomes
cost-effectiveness analysis
- disease specific outcome measures
- life-years gained
- quality of life
cost-effectiveness analysis
1. disease specific outcome measures
e. g. severity of depressive symptoms
- no comparison possible with other disorders
- relevant for health care providers
cost-effectiveness analysis
2. life-years gained
- hard to measure
- follow-up is not until you die
- we don’t expect that anxiety or a lot of other disorders contributes to life expectancy
- possible to compare all interventions that aim to extend life
- health has 2 aspects: duration and state
cost-effectiveness analysis
3. quality of life
- functioning, wellbeing, mental and physical, vitality… –> includes multiple domains
- when does a person improve? (some domains improved, some got worse, some stayed the same)
- hard to say
cost-utility analysis
- effects expressed in quality-adjusted life-years
- QALY= number of years in perfect health
- combination of quality and quantity of life
QALY graph
y-axis: QoL = death, 1 = perfect health
x-axis: duration of life (years)
QALY advantages
- not disease specific
- relevant for health care policy makers
- comparisons possible between all kinds of disorders and treatments
QALY Formel
QALY = V(Q) * Y
QALY negative values
- QoL is so bad, that you’d rather be dead
measuring utilities
- profiles rated by society (large sample!) to determine coefficients
- not by individuals themselves, because they may overestimate or underestimate the impact & whole society pays (we are all potential patients)
- EQ-5D-5L questionnaire filled out by patient
- -> compare baseline vs. after e.g., 3 mo with intervention
EQ-5D-5L
- often used questionnaire –> patients indicate their QoL
- 5 domains:
1. mobility
2. self-care
3. pain/ discomfort
4. anxiety/ depression
5. ability to do usual activities - -> how are the changes/decrements rated by society?
cost-benefit analysis
- effects expressed in monetary units
- benefits > costs?
- difficult to put a money value on health: how much money would you be willing to pay for 1 recovered patient extra?
2 types of economic evaluations
- mathematical model
2. conducted alongside an RCT (“Piggyback” design)
choice of comparator treatment
- primarily aimed at informing health care decision makers
- control should be an implemented treatment in actual current practice
- usual care
- standard care
- most commonly used treatment (can be no treatment)
- placebo is not a good comparator (you don’t use it in usual care and you might overestimate the effects of your treatment)
choice of perspective
- which cost categories should be included:
1. society
2. health care insurer
3. health care provider
4. patient
5. company
…
choice of perspective: societal perspective
- standard
- all costs and benefits are taken into account regardless of who pays or benefits
more choices to make if you want to do economic evaluation alongside RCT
- time horizon should be long enough to capture full consequences of the intervention (end point of interest& consequences)
- patients typical of the normal caseload are enrolled (resemble patients that you see in practice)
- physicians and patients are not blinded (not done it practice)
- patients are followed under routine conditions (no extra blood tests etc.)
- effectiveness rather than efficacy
cost categories
- health care costs –> costs within the formal healthcare sector
- patient costs –> costs paid by patients themselves
- lost productivity costs
- other costs
- medical costs in life-years gained
- costs of special schools
- justice and police costs
- … –> depending on situation and population
healthcare costs
- generally include costs that are reimbursed by the health care insurer, e.g. GP, laboratory tests, psychologist, medication …
patient costs
- costs that patients pay for themselves. e.g. complementary medicine, informal care, time and travel costs
lost of productivity costs
- days absence from paid work
- being present at work but not fully productive
- hours of being unable to perform daily activities, e.g. housekeeping, study or voluntary work
other costs
- medical costs in life-years gained, measurement impossible, so estimation necessary, only relevant in interventions that extent life or in prevention programs
cost diary
- often filled out retrospectively
- -> not so accurate
now: questionnaires: how many times did you visit the GP? etc.
balance: number of questionnaires, length of recall periods
how to value resource use
- if available: standard costs
- list of costs available in a lot of countries
- cost price calculations are very time-consuming (only done for large impact items)
ICER
= Incremental Cost-Effectiveness Ratio = incremental costs per incremental unit of effect
= Costs intervention- costs control/ effects interventions - effects control
ICER be aware
- only the ICER does not give enough information!
- information needed on size and direction of cost and effect differences (can be more expensive and more effective but also less expensive and less effective)
Interpretation ICER
… to gain 1 QALY in the intervention group …Euros needs to be invested in comparison with the medication group
cost-effectiveness plane
y-axis: incremental costs x-axis: incremental effects 4 quadrants: 1. low right: dominant 2. up left: dominated 3 and 4. : Trade-off: Are the additional effects worth the extra costs? Are we willing to trade off some effects to save money? --> you plot ICER in the plane
When is an intervention considered cost-effective in comparison with the control treatment? decision rule
ICER < maximum amount of money society is willing to pay per uni or effect extra (ceiling ratio)
What should the ceiling ratio be?
- as we increase the ceiling ratio, the proportion of dots in the cost-effectiveness area increases too –> probability of cost-effectiveness increases
cost-effectiveness acceptability curve
- shows the probability that an intervention is more cost-effective than its comparator for different ceiling ratios
- represents the decision uncertainty in cost-effectiveness analysis by showing the decision-maker the probability they have made the wrong decision if they decide to adopt a particular intervention
- -> the more value of ceiling ratios, the higher probability of cost-effectiveness
