Modeling finds infant Duffy testing cost-effective across scenarios

The study used a Markov cohort model to compare serologic Duffy testing with no testing alongside recommended blood work at 9 to 12 months of age. It took a US societal perspective over a lifetime horizon and modeled different levels of diagnostic workup for neutropenia. The primary outcome was incremental net monetary benefit (iNMB) per child tested.

Duffy testing was favored in the base case and all scenario analyses, with iNMB ranging from $2.18 to $92.77 per child. In 10,000 probabilistic iterations, universal testing was favored in 95% to 100% of runs across the scenarios. The cost of testing, the cost of neutropenia workup, and the prevalence of low absolute neutrophil counts had the greatest influence on results. The modeled Duffy-null prevalence thresholds for cost-effective universal testing varied by scenario, from 1.3% to 9.0%; the threshold for targeted testing was 4.9%.

These are model-based economic findings, not evidence that testing improves clinical outcomes. Results are sensitive to assumptions, and the full article was not available in the supplied source. The authors report that the prevalence thresholds would support cost-effective implementation in at least 20 US states.