Probabilities

Question 1

Probabilities

Answer 1

• Likelihood of events or changes in health

- Decision analysis model is set of values bound together by collection of probabilities

Question 2

Probability Rules

Answer 2

1. Events must be mutually exclusive and independent
2. Complement Rule: probabilities add up to 1
3. Multiplicative Rule: Product of probabilities is the probability of multiple, sequential, independent events

Question 3

Expected Value

Answer 3

• Probability of event * Value associated with event
• Of a scenario is the sum of these products
• IF there is a treatment cost applicable to everyone, then add that to the rest of the summations

Question 4

Expected Outcomes

Answer 4

• QALYs * Probability

- Can give you an overall estimation of QALY for a particular scenario

Question 5

Sources for Economic Evaluation

Answer 5

• All sources for valuation of costs, benefits, and utilities should be clearly state in article
• Evidence used for assumptions should be relevant to the population and the study question
• Use a micro-approach and existing information for estimates

Question 6

Costs

Answer 6

• Accurate assessment of costs takes time and effort
• Want a fair representation of values
• Level of precision can depend on degree outcomes occur in study
• Most precise: DRG
• TRY to use disease-specific cost when possible

Question 7

Outcomes

Answer 7

• Based on clinical trials

- Affected by size of trial, study period, number of trials, generalizability

Question 8

Utility and HRQOL Values

Answer 8

• Utility values obtained from direct or indirect elicitation
• HRQOL obtained from generic instruments or disease specific ones
• Need to take note of size surveyed, how recent the estimates are, and if one or multiple sources were used