Purpose: Clinical trials include a series of eligibility and exclusion criteria that define the study population to reduce inter-patient heterogeneity and increase safety. Little is known about children with oncological diseases excluded from trials because they do not satisfy these criteria. We analysed the eligibility criteria adopted in the European paediatric Soft tissue sarcoma Study Group RMS2005 study and the survival of non-eligible patients. Patients and methods: RMS2005 run from 10/2005–12/2016. Eligibility criteria were age ≤ 25 years; pathologically proven diagnosis of rhabdomyosarcoma (RMS); no evidence of metastases; no pre-treatment; no pre-existing conditions preventing treatment; no previous malignant tumours and an interval between diagnostic surgery and the start of treatment ≤ 8 weeks. Clinical characteristics, 5-year progression-free survival (PFS), and overall survival (OS) were analysed for eligible and non-eligible patients. Results: The 79 non-eligible patients (4.3% of registered patients) were older than eligible patients (p