Figure 5.

Selected clinical and immunological characteristics that better distinguish pandemic influenza A(H1N1) from COVID-19. (A) Linear discriminant analysis (LDA) plot of the first two discriminant functions showing the separation of the different groups of study participants according to a set of selected clinical and immunological characteristics used in combination. Each dot represents a single individual, and each color represents a group of participants: blue for pandemic influenza A(H1N1), orange for moderate COVID-19, and red for severe COVID-19. (B) Accuracy of the LDA results before and after a “leave-one-out” cross-validation. (C) The discriminant potential of each individual variable included in the LDA was estimated using the Wilk´s Lambda test. The table displays values of Wilk´s lambda, F, and p for each variable.