A comparison of the three search tools, based on measures quality, precision and recall. The higher scores for CRT and Pilercr show that automatic detection of CRISPRs can be very reliable, even more so than with the use manual post-processing as is done with Patscan. The results in the left half of the table are for CRISPRs containing Cas genes. Because the authors suspect that CRISPRs with Cas genes have fewer mutations, and are thus easier to detect, a second experiment was performed using randomly selected finished genomes. The results of this second experiment are shown in the right half of the table. As expected, slightly lower scores resulted, and they should better reflect the effectiveness of the tools.