Variable Selection and Model Development
Together with previous clinical researches, according to the results of
the LASSO regression model and the multivariable logistic regression
model, nine of the 22 variables were selected as the potential
predictors of tophi formation (Figures 1A and 1B ). These
variables were hospitalisation frequency, disease duration, number of
joints involved in gouty arthritis, gout flares frequency, smoking, and
whether combined with atherosclerosis, diabetes, hypertension and kidney
dysfunction. The logistic regression analysis results of these variables
are shown in Table 2 . A prediction model that contains the
above predictors was then developed and represented as a nomogram
(Figure 2 ).