Comparative effectiveness of a rapid point-of-care test for detection of Chlamydia trachomatis among women in a clinical setting

Abstract

Objectives: To compare the effectiveness and cost-effectiveness of a promising new point-of-care (POC) chlamydia test with traditional nucleic acid amplification testing (NAAT), and to determine the characteristics that would make a POC test most cost-effective.

Methods: A decision tree was constructed to model chlamydia screening visits to a sexually transmitted disease clinic by a hypothetical cohort of 10,000 women. The model incorporated programmatic screening costs, treatment costs and medical costs averted through prevention of pelvic inflammatory disease (PID) and its sequelae. Parameter values and costs were estimated for each node in the decision tree based on primary data, published data and unpublished health data.

Results: For the base-case scenario (POC sensitivity 92.9%; 47.5% of women willing to wait 40 min for test results; test cost $33.48), POC was estimated to save US$5050 for each case of PID averted compared with NAAT. One-way sensitivity analyses indicated that POC would dominate NAAT if the POC test cost is <US$41.52 or if POC sensitivity is ≥ 87.1%. In a probabilistic sensitivity analysis (Monte Carlo simulations, 10 000 iterations), 10.8% of iterations indicated that the POC strategy dominated the NAAT strategy. The mean incremental cost-effectiveness ratio indicated that the POC strategy would save US$28 in total, and avert 14 PID cases.

Conclusions: A promising new chlamydia POC test is likely to be cost-effective compared with traditional NAAT. The POC test sensitivity, cost and proportion of women willing to wait for the POC test result are key elements to determining the cost-effectiveness of any new POC test strategy.

Figure 1

Using point estimates, point-of-care (POC) is more cost-effective than nucleic acid amplification testing when the three parameters examined (POC test cost, POC sensitivity, percentage of women willing to wait for the test result) fall in the dark grey region. The dashed lines show the base case for sensitivity (92.9%) and 40 min waiting time (47.5% of women waited).

Figure 2

Acceptability curve comparing the cost-effectiveness of point-of-care versus nucleic acid amplification testing based on a Monte Carlo simulation (10 000 iterations). PID, Pelvic Inflammatory Disease.