Figure 1.

Decision tree of CDI diagnostic strategies. a Decision tree of NAAT alone. b Decision tree of two-step diagnostic strategies. Antimicrobial treatment: patients who had positive tests or false-negative tests would be treated. Following treatment, patients were either deemed cured, death, or a treatment failure. Patients who failed to response to the current treatment would receive next-line treatment. Patients who were deemed cured would either cured without recurrence or develop recurrence. Recurrence was assumed that patients successfully treated who then developed a recurrence at least 4 weeks later. We modeled up to two recurrences. Within the decision tree, patients were modeled in one of six health outcomes: healthy without CDI (true negative), cured (without further recurrence) from mild-moderate CDI, cured (without further recurrence) from severe CDI, a mild-moderate post-colectomy health condition, a severe post-colectomy health condition, and death. CDI,Clostridioides difficileinfection; NAAT, nucleic acid amplification test.