  Importance: An artificial intelligence (AI)-based model to predict COVID-19
likelihood from chest x-ray (CXR) findings can serve as an important adjunct to
accelerate immediate clinical decision making and improve clinical decision
making. Despite significant efforts, many limitations and biases exist in
previously developed AI diagnostic models for COVID-19. Utilizing a large set
of local and international CXR images, we developed an AI model with high
performance on temporal and external validation.
  Conclusions and Relevance: AI-based diagnostic tools may serve as an adjunct,
but not replacement, for clinical decision support of COVID-19 diagnosis, which
largely hinges on exposure history, signs, and symptoms. While AI-based tools
have not yet reached full diagnostic potential in COVID-19, they may still
offer valuable information to clinicians taken into consideration along with
clinical signs and symptoms.
