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A technique for approximating transition rates from published survival analyses.
Markian A Pahuta1, Joel Werier2, Eugene K Wai2,3
11Department of Orthopaedic Surgery, Henry Ford Health System, Detroit, MI USA.
Cost Effectiveness and Resource Allocation : C/E
|July 16, 2019
Summary
This study introduces a novel method to estimate transition rates for health economic models using progression-free survival (PFS) and overall survival (OS) data. This approach enables more accurate quality-adjusted life-year (QALY) calculations when detailed multistate modeling data is unavailable.
Area of Science:
- Health economics
- Biostatistics
- Survival analysis
Background:
- Quality-adjusted life-years (QALYs) are crucial for evaluating treatment benefits and risks.
- QALYs are commonly calculated using partitioned-survival or state-transition models.
- State-transition models require transition rates, often derived from multistate modeling (MSM).
- Estimating transition rates for state-transition models is challenging when only progression-free survival (PFS) and overall survival (OS) data are reported.
Purpose of the Study:
- To develop and present a method for estimating approximate transition rates from published PFS and OS analyses.
- To enable the use of flexible state-transition models for QALY calculations even with limited survival data.
- To provide a practical approach for health economic evaluations.
Main Methods:
- Developed a novel approximation method to estimate transition rates from PFS and OS data.
- Distinguished between approximate transition rates and true transition rates (from full MSM).
- Applied the method to a case study and evaluated its performance in a simulation study.
Main Results:
- The approximation method provides reasonable estimates for transition rates, particularly for transitions out of health.
- The method tends to underestimate true transition rates as the level of censoring in the data increases.
- Accuracy is influenced by the extent of data censoring.
Conclusions:
- The presented method offers a viable approach to derive essential transition rates for state-transition models when full MSM data is unavailable.
- This facilitates more robust QALY calculations in health economic evaluations.
- The method's performance is dependent on data characteristics, particularly censoring.
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