To find probability values in CEA, you can use different sources of data, such as clinical trials, observational studies, expert opinion, or literature reviews. The type and quality of data you use will depend on the availability and relevance of the information for your specific decision problem.
Here's an example of how to find probability values in CEA using a model dataset:
Suppose you are comparing two interventions for the treatment of a particular disease: Intervention A and Intervention B. You have collected data from a randomized controlled trial that compares the two interventions in terms of their effectiveness and adverse effects.
The following table summarizes the data:
Outcome Intervention A Intervention B
Improved health 80 patients 70 patients
No improvement 20 patients 30 patients
Adverse effects 10 patients 20 patients
To estimate the probability of each outcome for each intervention, you can calculate the proportion of patients who experienced that outcome:
The probability of improved health with Intervention A = 80 / (80 + 20) = 0.80 or 80%
The probability of no improvement with Intervention A = 20 / (80 + 20) = 0.20 or 20%
The probability of adverse effects with Intervention A = 10 / (80 + 20) = 0.10 or 10%
Similarly, for Intervention B:
The probability of improved health with Intervention B = 70 / (70 + 30) = 0.70 or 70%
The probability of no improvement with Intervention B = 30 / (70 + 30) = 0.30 or 30%
The probability of adverse effects with Intervention B = 20 / (70 + 30) = 0.20 or 20%
Once you have estimated the probabilities for each outcome, you can use them to calculate the expected value of each intervention in terms of both costs and outcomes. This allows you to determine which intervention is most cost-effective and provides the best outcomes for patients.