Fig. 1. COVID-19 diagnosis performance results across different UK NHS Trusts.

Panels compare performance of basic (standalone) and adversarial models (blue and red, respectively) during prospective validation (a OUH) and external validation (b PUH, c UHB, d BH). Adversarial models were trained to mitigate ethnicity biases. All models were optimized during training to achieve sensitivities of 0.9. Error bars show 95% confidence intervals. Numerical results are shown in Supplementary Table 3.