Health Economics Information Resources: A Self-Study Course

Module 4: An Introduction to the Principles of Critical Appraisal of Health Economic Evaluation Studies

Key areas for critical appraisal - 5. Sensitivity analysis

Economic evaluations are models which attempt to capture and summarize reality. These models use assumptions and estimates.

Sensitivity analysis tests the robustness of the conclusions by repeating the comparison between inputs and consequences while varying the assumptions used. Given that there will be a degree of uncertainty about some elements of any economic evaluation, sensitivity analysis assists in judging how robust the conclusions will be.

The main candidates for sensitivity analysis in economic evaluation are:

• values not measured - because they are difficult to collect
• imputed (assigned, attributed) values - because the true opportunity cost is not known
• the discount rate - because time preference may be important but the degree of importance is not known
• the confidence limits of a statistical estimate of a variable
• estimations of survival or quality of life - particularly in the extrapolation of outcomes

Summary

In this module you have learned that:

• The quality of published health economic evaluations is variable and their reporting can be inadequate
• Health care decision makers need to be sure that the evidence on efficiency is reliable and can be applied to their own situation
• Checklists for quality assessment which cover the key areas for critical appraisal are widely available
• The uncritical use of economic evaluation study results should be avoided - ALWAYS CRITICALLY APPRAISE!

Previous

Test Yourself

Next