Fig. 3
From: A study of SPECT/CT camera stability for quantitative imaging
Graph of the conversion factors for 99mTc complete data set over the entire 18 months of the study. Data set includes all phantoms, 20 cm, ACR, and IQ (solid diamond) and all liter bottles: 1 (circle)-, 2 (triangle)-, and 4 (square)-L. 72.5 % of the data points are within one standard deviation of the mean