Fig. 4From: Selected serum cytokines and nitric oxide as potential multi-marker biosignature panels for Parkinson disease of varying durations: a case-control studyDensity distribution of permutated AUC values compared to the normal distribution. The significance of real AUC value for (a) less than 1 year of PD, (b) 1–3 years of PD and (c) 3–12 years of PD. The‘real AUC values’ lie outside the permutated AUC distribution that symbolise high validity of the marker panels generated via CombiROCBack to article page