Compute relative bias (%) as (x − x_ref)/x_ref × 100% to evaluate the relative level of measurement deviation.
输入测得值与参考标准值，求相对偏倚。
| Item | Formula / Note | Source / Standard |
|---|---|---|
| Relative bias | Relative bias = (xbar - x_ref)/x_ref × 100% | ISO 5725-1:1994, Accuracy (trueness and precision) of measurement methods - Part 1 |
| Relation to recovery | Recovery = measured/reference × 100%; relative bias = recovery - 100% | AOAC International, Guidelines for Single Laboratory Validation of Chemical Methods |
| Traceability of the reference | The reference value must be traceable to national or international standards | ISO/IEC 17025:2017, General requirements for the competence of testing and calibration laboratories |
| Compliance criterion | Compare against the maximum permissible error specified by the method | ISO 5725-1:1994, Accuracy (trueness and precision) of measurement methods |