A system for reporting analytical results according to the actual level of the test's exactitude

The number of significant digits, or better the increment by which a result is increased to the next highest figure, has to be related to the precision of the analytic procedure. If the relative increment is much smaller than the precision, the last digits are meaningless, and if it is too large, information contained in the result is lost. A system based only on a determined number of digits in a report is inefficient as the relative increment varies within too wide a range of 10 to 1. In the proposed system, the increment and the range of values to which this increment applies are determined. The two limits of the range are set as fractions of the 95% limits of confidence so that at mid-range, half of the results have better precision and half less than the relative increment. A Table gives the increments to be used for various ranges of results between 0.001 and 1000 units and for precision between 2% and 12%. The system produces realistic reports for every level of analytical precision and its application is simple. It also permits to take into account changes of precision at the extremes of low or high values.