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
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!