The 'Noise filters' examine each candidate variant at a more detailed level. They are intended as a means of filtering out variants that are likely to be the result of various types of systematic errors and/or biases, e.g. induced by the amplification or sequencing protocol, that may occur in samples. They should be used with care, as there is always the risk that a real variant has the characteristics of systematically induced variant.
Figure 27.21: Noise filters.