Cost Effectiveness of the Reverse Sequence Algorithm Compared With the Traditional Algorithm for Syphilis Screening...

Area of Science:

• Medical Diagnostics
• Public Health
• Health Economics

Background:

• Traditional syphilis screening uses a nontreponemal assay followed by treponemal testing.
• The reverse sequence algorithm alters this order and adds a second treponemal test for discordant results.
• Operational advantages of the reverse sequence necessitate cost-effectiveness evaluation.

Purpose of the Study:

• To conduct a cost-effectiveness analysis comparing the reverse sequence and traditional syphilis screening algorithms.
• To evaluate the economic impact of each algorithm from a healthcare sector perspective.
• To assess the cost per quality-adjusted life-year (QALY) gained for the reverse sequence algorithm.

Main Methods:

• Decision tree modeling for pregnant women in prenatal care, including congenital syphilis outcomes.
• Simulation of a 10,000-person cohort screened over one year.
• Calculation of incremental cost-effectiveness ratios (ICERs) and sensitivity analyses.

Main Results:

• The reverse sequence detected more syphilis cases but led to significant overtreatment.
• The ICER for the reverse sequence was $463,735/QALY gained, indicating poor cost-effectiveness.
• Syphilis prevalence critically influences ICERs, requiring >6% prevalence for favorable cost-effectiveness.

Conclusions:

• Under typical conditions, the reverse sequence algorithm is not cost-effective compared to the traditional approach.
• Increased overtreatment costs negate potential laboratory savings from treponemal test automation.
• The traditional syphilis screening algorithm remains the more economically viable option.