ROC curves for prediction of ICD incidence in patients using dopamine agonists. The red ROC curve was plotted with clinical variables only (age, gender, DRT and duration of follow-up period). The blue ROC curve was plotted with clinical and genetic variables combined. The genetic variables consisted of genotype data on 13 preselected SNPs. p Value refers to AUC comparison of the two curves. AUC, area under the curve, DRT, dopamine replacement therapy; ICD, impulse control disorders; ROC, receiver operating characteristic SNPs, single nucleotide polymorphisms.