The false positive and false negative results are summarized by schedule in a data table. The green line on the chart describes the analyte reporting level.
The false positive and false negative charts display all concentration results, and false positives are represented by a red asterisk and false negatives are
represented by a red down arrow.
A list of false positives and false negatives below the chart summarizes the false positive and false negative results and provides expected concentration and result
concentrations for every analyte for every schedule OBSP assesses.
A false positive result - when an analyte is reported by the laboratory when it is not present in the sample. False positives can result from random variability in background
response, contamination, or misidentification of the analyte.
A false negative result - the analyte is present in the sample but it is not reported by the laboratory. False negatives can arise from random variability, lower than normally expected
recovery, or misidentification of the analyte.
U.S. Department of the Interior |
U.S. Geological Survey
