Difference in methylation status of indicated genes (% units) among clinical variables in NB patients. Global P value tests the hypothesis of equal methylation status in both groups. (A) Stages M - MS vs. L1-L2. (B) Patients younger than 18 months at diagnosis vs. patients older than 18 months at diagnosis. (C) MYCN-amplified patients vs. patients with no-MYCN amplification. (D) Patients with events (relapse/death) vs. patients without events.