Cost Utility Analysis Flashcards
What does CUA measure?
Measures costs in dollars ($$$) & outcomes in health utilities (i.e., QALY or quality-adjusted life year)
What is QALY?
Heath utility that accounts for the patients quality and quantity of life
* Years of life are adjusted by utility weights ranging from 0-1
* Utility weights are assigned based on patient or societal preferencces for certain disease states
What are the advantages of CUA?
- Multiple health outcomes can be compared using one common unit (QALYs) without assigning monetary value
- CUA should be used when morbidity and mortality are important health outcomes associated with a treatment
What are the disadvantages of CUA?
Difficult to determine an accurate QALY value
What are the steps of calculating QALYs?
- Develop a descrioption of each disease state or condition of interest
- Choose a method for determining utilities
- Choose subjects who will determine utilities
- Multiply the utility scores by the length of life for each option to obtain QALYs
How do you Develop a description of each disease state or condition of interest?
- Concisely describe the usual health effect associated with a disease state
- Include elements of a certain disease state or medical condition
What are the elemetns of certain disease state or condition?
- Amount of pain and discomfort
- Restrictions on normal daily activities
- Time necessary for treatment
- Possible changes in health perception
- Mental health changes
What are exampoles of Developing a description of each disease state or condition of interest.
- Hospital based kidney dialysis
- Diabetic retinopathy
What are common methods for determining utility weights?
- Rating scale
- Standard gamble
- Time tradeoff
What is a rating scale?
- One line on a page with scaled marking from 0-100
- Subjects receive descriptions about different disease states or conditions
- Subjects rate their estimated preferences on the rating scale
What are the advantages of a rating scale?
- Describes multiple disease states in one RS eval
- Preformed remotely via questionnaire
- General public’s familiarity with rating preferences
What are the disadvantages of RS?
- Dont incorporate time into utility score, when compared to SG or TTO
- Posible bias in preferences
* Tendency not to rate utility near 0 or 1
* Tendency to rate preferences throughout given range - Participants dont rank preference choices between options
What is a standard gamble?
Method where participants offter alternatives:
1. Alternative 1: treatmetn with 2 potential results of retunring to normal or immediate death
2. Alternative 2: certain outcomes of disease state for life based on life expectancy
Probability of normal health measured by p
Immediate death measured by 1-p
Probability of normal health is varied unntil participants reach a point of indifference between alternatives 1 and 2
What are the advantages of SG?
Gold standard method on economic theory
What are the disadvantages of SG?
- Difficult for participants to complete (more cognitively demanding than RS)
- Appropriate only to administer in face-to-face matter (necessary to ask reptitive questions, requires resources)
What is time tradeoff?
Alternative 1: specific disease state for specific length of time (t)
* Time (t) = life expectancy of a patient with the specific disease state
Alternative 2: being healthy for time x, which is less than t
How do you calculate a utility score?
Utility score = 𝑥/𝑡
What are the advantages of TTO?
- More adaptable to disease state than SG method
- Uses time in the disease state more easilty than RS method
What are the disadvantages of TTO?
- Difficult for patients to complete
* More cognitively demanding than RS method - Appropriate only to adminsiter in face to face matter
* Necessary to ask repetitive questions
* Requires more resources to perform, when compared to RS questionnaire
What are the advantages and disadvantages of choosing patients with specifc diseases to determine utilities?
Advantages: Better understand effects of disease
Disadvantages: potential bias when rating preferences for specific disease
Patient with specific disease rate ___ utility scores than general public because?
Higher due to patients’ adaptability & adjustments for living with disease
Who determines utility scores for patients?
Caregivers
What are the advantages and disadvantages of choosing healthcare providers to determine utilities?
Advantages:
* Good understanding about numerous disease states
* Easily accessible for interviews
Disadvantages:
* Potential bias not to rate pain, discomfort or disability lower on preferences, when compared to patients’ rating
What are the disadvantages of choosing society providers to determine utilities?
- Lack of familiarity with effects associated with a specific disease
- Descriptions of specific diseases may not cover all issues associated with the condition
- More time & labor demanding
- More cognitively demanding on general public, if all issues associated with condition are discussed in the description
