Laboratory Bias Evaluation

ASTM International’s rubber and rubber-like materials committee (D11) is working on a proposed standard to address variation between laboratories resulting from bias.

The standard guide (WK85445) is part of the lineage formed by D4483, which has helped committee members improve testing precision within labs over the past several decades. However, according to John Bailey, chair of the committee’s application of statistical methods subcommittee (D11.16), the issue of variation between labs persists.

“Differences in testing between laboratories can contribute to complaints, rejection of shipments, and increased quality costs,” says Bailey, president of OkStats, Inc. “Manufacturers and end-users can utilize this guide to evaluate the magnitude of bias in their test results. Applying this knowledge, they can implement remediation programs to begin to determine the sources of bias.”

Bailey notes that the guide is intended to begin a larger discussion of the evaluation of bias in rubber and carbon black test methods.