Several mineralization methods for the determination of selenium using hydride generation optical emission spectrometry with inductively coupled plasma in biological samples (whole egg powder and pork liver) were compared using the analysis of means (ANOM) method. This statistical tool is suitable for graphical representation of testing on simple comparative experiments. The results yielded by ANOM are identical with those obtained with the commonly used analysis of variance (ANOVA) method; however, the graphical output of ANOM is more illustrative in comparison to ANOVA. Both methods indicated a significant discrepancy between the results obtained using muffle furnace ashing mineralization and the results provided by other mineralization methods. This is probably due to the loss of volatile selenium compounds during the decomposition of organic matter.