Where does margin collide?

In surgical oncology the margin is the rim of apparently normal tissue that a surgeon removes around a tumour, whose edge the pathologist then examines: a margin is called negative or clear when no cancer cells reach the inked surface of the excised specimen, and positive when they do, which usually calls for more surgery. Moran and colleagues' 2014 consensus guideline on margins for breast-conserving surgery defined an adequate margin for invasive breast cancer as no ink on tumour and weighed how wider margins do and do not change recurrence. The referent is a physical border of excised tissue, judged in millimetres under a microscope, and it is unrelated to a marginal unit, borrowed money, a poll's error band, or the edge of a field.[1]

Unit

The distance from tumour to the inked edge of the excised tissue, in millimetres

Recovery means

Not applicable

Measured by

Assessed by a pathologist, who inks the specimen surface and reports the margin as negative or positive

In survey statistics the margin of error is the half-width of a confidence interval around an estimate made from a sample: it says how far the reported figure might sit from the true population value by sampling chance alone, so a poll at 48 percent with a margin of error of 3 points spans roughly 45 to 51 percent. Larson's 2003 Misunderstanding margin of error examined how television news coverage of election polls reported and, often, misread this band. The referent is a quantified bound on sampling uncertainty, expressed in percentage points at a stated confidence level, and it does not name a marginal unit, a broker's loan, a rim of tissue, or an uncultivated strip beside a field.[2]

Unit

A bound on sampling error, in percentage points at a stated confidence level

Recovery means

Not applicable

Measured by

Calculated from the sample size, the estimate, and a confidence level, as the half-width of the interval