In this study, data on charged-pion production in relativistic oxygen-ion collisions are examined with varying degrees of centrality. Using the multiplicity of producing charged pions, it is proved that there is a relationship between centrality degrees and collision parameters (such as the impact parameter b, target size fragments, Nh and the total charge of projectile spectators, Q. The various order moments of the multiplicity distributions are used in the standard way to investigate the underlying correlations. The evidence suggests that all the pions produced at the various target sizes (Nh-values) correlate. The higher moments are also investigated at various centrality classes decided by the parameter Q. The multiplicity fluctuations, as measured by the variance-to-mean ratio, showed that the multiplicity distributions of produced pions are not Poissonian, regardless of how they were examined using the two parameters Nh and Q-values.