Figure 1From: Impact of inherent variability and experimental parameters on the reliability of small animal PET data Experimental design of homogenization vs. heterogenization. The scheme of the experiment is in analogy to the study of Richter et al. [7]; 8 × 8 animals underwent 18F-FDG scans according to PET protocol 1. Varying experimental parameters were gender, age, and cage occupancy of the animals (n = 2 or n = 13 per cage). Animal groups were divided according to gender. This setup allowed for four strictly homogenized test group comparisons with the only parameter varying being gender (one example of such a comparison pair is indicated in dark gray). On the other hand, by reordering the same data into 8 × 8 randomized groups, four comparisons of such pseudo-heterogenized groups were performed (indicated by the light grey squares).Back to article page