Cost-Effectiveness Analysis of Four Common Diagnostic Methods for Clostridioides difficile Infection

Area of Science:

• Health Economics
• Infectious Diseases
• Diagnostic Test Evaluation

Background:

• Cost-effectiveness of Clostridioides difficile infection (CDI) diagnostic strategies is not well-established.
• Direct and indirect costs associated with CDI diagnosis require evaluation.

Purpose of the Study:

• To assess the cost-effectiveness of single and two-step diagnostic tests for CDI.
• Evaluate nucleic acid amplification testing (NAAT) alone, glutamate dehydrogenase followed by enzyme immunoassay for toxin (GDH/EIA), GDH then NAAT (GDH/NAAT), and NAAT then EIA (NAAT/EIA).

Main Methods:

• A decision tree model was utilized from a US societal perspective.
• Model inputs were derived from existing literature.
• Sensitivity analyses (one-way and probabilistic) were performed to assess input uncertainty.

Main Results:

• NAAT alone emerged as the most cost-effective overall strategy.
• GDH/NAAT was identified as the most cost-effective two-step approach.
• NAAT alone yielded the highest quality-adjusted life years (QALYs) gained across comparisons.

Conclusions:

• NAAT alone represents the optimal cost-effective diagnostic approach for CDI.
• GDH/NAAT is the most cost-effective among the evaluated two-step strategies for CDI diagnosis.