  We present an explicit analytical computation of the quantum corrections, at
next-to-leading order, to the critical exponents. We employ for that the
Unconventional minimal subtraction, recently proposed, and the Callan-Symanzik
methods to probe the universality hypothesis by comparing the outcomes for the
critical exponents evaluated in both methods and the ones calculated previously
in massless theories renormalized at different renormalization schemes.
Furthermore, the consistency of the former method is investigated for the first
time in literature, to our knowledge. At the end, we compute the critical
exponents at any loop level by an induction process and furnish the physical
interpretation of the results.
