Table 1

Calculation of Sensitivity and Specificity depending on ECAD expression ("2x2 table").

"gold standard" = result of sentinel node biopsy


occult metastatic disease: Yes

occult metastatic disease: No


new predictive marker for occult metastatic disease (ECAD)

Low ECAD

true positive

false positive

all test positives

expression

a

b

a + b

High ECAD

c

d

all test

expression

false negative

true negative

negatives

c + d


a + c

b + d

all with occult

all without occult

disease

disease


Hypothesis: low ECAD expression (test) predicts occult metastatic disease

sensitivity: a/(a + c)

specificity: d/(b + d)

Huber et al. BMC Cancer 2011 11:217   doi:10.1186/1471-2407-11-217

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