Define Minor Error in AST method comparison.

Define Minor Error in AST method comparison.

• A. A discrepancy involving intermediate vs susceptible or resistant.
• B. A discrepancy involving two different species.
• C. A minor numerical mismatch in MIC values within one dilution.
• D. A major shift in zone diameter.

Answer: (A)

In antimicrobial susceptibility testing, results are interpreted as susceptible, intermediate, or resistant. When two methods are compared, errors are defined by how these interpretive categories align. A minor error happens specifically when the intermediate category sits between susceptible and resistant, so a discrepancy where one method reports intermediate while the other reports susceptible or resistant fits this definition exactly. This captures that the disagreement involves the gray area of intermediate results rather than a straightforward swap between susceptible and resistant. So, if a test method yields intermediate and the reference method yields susceptible, or the reference yields resistant, that’s a minor error. The other options describe situations that aren’t about this interpretive mismatch: a discrepancy between species isn’t an AST method comparison error, a small numeric MIC difference within one dilution doesn’t necessarily change the category, and a major shift in zone diameter would be a Major or Very Major error rather than Minor.

In antimicrobial susceptibility testing, results are interpreted as susceptible, intermediate, or resistant. When two methods are compared, errors are defined by how these interpretive categories align. A minor error happens specifically when the intermediate category sits between susceptible and resistant, so a discrepancy where one method reports intermediate while the other reports susceptible or resistant fits this definition exactly. This captures that the disagreement involves the gray area of intermediate results rather than a straightforward swap between susceptible and resistant.

So, if a test method yields intermediate and the reference method yields susceptible, or the reference yields resistant, that’s a minor error. The other options describe situations that aren’t about this interpretive mismatch: a discrepancy between species isn’t an AST method comparison error, a small numeric MIC difference within one dilution doesn’t necessarily change the category, and a major shift in zone diameter would be a Major or Very Major error rather than Minor.