Previous health economic studies recommend either a dual screening strategy [tuberculin skin test (TST) followed by interferon-gamma-release assay (IGRA)] or a single one [IGRA only] for latent tuberculosis infection (LTBI), the former largely based on claims that it is more cost-effective. We sought to examine that conclusion through the use of a model that accounts for the additional costs of adverse drug reactions and directly compares two commercially available versions of the IGRA: the Quantiferon-TB-Gold-In-Tube (QFT-GIT) and T-SPOT.TB.
Division of Infection and Immunity, Centre for Infectious Diseases and International Health, University College London Medical School, University College London, 43 Cleveland Street, London W1T 4JF, UK.