Cost-effectiveness analysis in colorectal cancer using a semi-Markov model

Area of Science:

• Health economics
• Biostatistics
• Oncology

Background:

• Traditional cost-effectiveness models often simplify patient health dynamics.
• There is a need for methods that incorporate dynamic health status changes into cost assessments.
• Colorectal cancer follow-up strategies require robust cost-effectiveness evaluation.

Purpose of the Study:

• To develop and apply an original semi-Markov model for assessing total patient costs.
• To incorporate patient health status dynamics and covariate effects into cost modeling.
• To perform a cost-effectiveness analysis comparing two colorectal cancer follow-up strategies.

Main Methods:

• Developed a semi-Markov model with explicitly defined sojourn time distributions (Weibull).
• Incorporated covariates into the hazard function for each transition.
• Derived a cumulative cost function from a regression model and used bootstrap for Incremental Net Benefit (INB) estimation.

Main Results:

• The model enabled estimation of mean cost per patient and identification of direct cost determinants.
• Mean survival differed between standard (4.35 years) and moderate (4.12 years) follow-up groups.
• Mean costs varied significantly based on follow-up strategy and Dukes stage.

Conclusions:

• The proposed semi-Markov model effectively integrates health status dynamics into cost analysis.
• Neither of the compared colorectal cancer follow-up strategies demonstrated superior cost-effectiveness.
• Follow-up strategy and cancer stage are significant determinants of direct medical costs.