With the Neurite Outgrowth application, both PC12 and Neuroscreen-1 cells can be used in robust, automated, compound screening assays. Figure 2 shows the Neurite Outgrowth Index versus well number from plates of PC12 and Neuroscreen-1 cells, where half of each plate was treated with NGF to induce neurite outgrowth. We calculated the Z-factor to evaluate if an assay is suitable for screening. The results shown in figure 2 gave Z-factors of 0.73 and 0.82, respectively, confirming these are "excellent assays" for screening with the separations between the negative and positive responses being much larger than three standard deviations.