Modelled probability of cutaneous squamous cell carcinoma (SCC) by PyV seroreactivity assessed in the baseline or earliest serum sample collected, with adjustment for continuous age, gender, and study center, in multivariable binomial generalized additive models (binomial GAMs) among 342 study participants from the Skin Cancer Prevention Study. The solid line represents the modelled probability of SCC, and the dashed lines denote the 95% confidence intervals. The rug along the x axis shows the distribution of study participants. The estimated degrees of freedom (edf) and corresponding significance is shown above each plot. The only smoothed (nonparametric) component of the binomial GAM was PyV seroreactivity.