Final Summary

The 1 % LPC failure rate represents a statistical property, not a controllable performance metric.
It emerges naturally when the assay’s mean and variance structure are stable and correctly characterized.

Key implications are as follows:

  1. Probability, not control:
    The 1 % rule defines an expected long-term proportion, not a run-by-run target to “fix.”
    Temporary deviations are part of the probabilistic process.

  2. Adjustment must be analytical, not arbitrary:
    When failure rates drift, the solution lies in variance analysis, not in raising LPC concentration.

  3. Statistical vigilance:
    Continuous observation of SCP distribution and LPC precision provides early warning of genuine analytical drift.

  4. Integrity through traceability:
    Maintaining statistical traceability ensures that assay performance remains defensible, reproducible, and regulatorily transparent.

In summary, the robustness of an ADA assay does not come from forcing the LPC to succeed, but from allowing its designed probability to manifest under a statistically stable system. At GCCL, we regard the 1 % rule as a test of analytical integrity—a benchmark that validates the system itself, not the analyst’s ability to adjust it.