Thanks for responding. The first study did find that severity is correlated with incidence of long COVID, and controlled as follows: “Propensity score 1:1 matching [19] (with greedy nearest neighbor matching, and a caliper distance of 0.1 pooled standard deviations of the logit of the propensity score) was used to create cohorts with matched baseline characteristics and carried out within the TriNetX network” My knowledge of statistical analysis is rather insufficient to evaluate the controls in that study, so hoping you or another commenter can chime in on that.
Thanks for responding. The first study did find that severity is correlated with incidence of long COVID, and controlled as follows: “Propensity score 1:1 matching [19] (with greedy nearest neighbor matching, and a caliper distance of 0.1 pooled standard deviations of the logit of the propensity score) was used to create cohorts with matched baseline characteristics and carried out within the TriNetX network” My knowledge of statistical analysis is rather insufficient to evaluate the controls in that study, so hoping you or another commenter can chime in on that.