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Table 1 Needed notation for the formulas of the different confidence intervals in Table 2

From: A modified Wald interval for the area under the ROC curve (AUC) in diagnostic case-control studies

Notation

Explanation

logit(AUC)=log AUC 1 - AUC

Logit transformation of the AUC

expit(·)= exp ( · ) exp ( · ) + 1

Back transformation of the Logittransformation

z = z 1-α/2

1-α/2 quantile of the normal distribution

s

Empirical standard deviation of AUC

se

Standard error of AUC by Bamber [8]

AUC =Φ ( X ¯ 1 - X ¯ 0 ) / s 1 1 + ( s 0 / s 1 ) 2

AUC for the binormal ROC curve (s i ,i = 0,1,as empirical estimator of σ i )

s

Empirical standard deviation of AUC

t= z 1 - α / 2 2 n

Factor for the Wilson interval

AUC ~ = AUC ̂ · n + 2 n + 4

Modified AUC (for the A-C interval)

k=round( AUC ̂ ·n)

Estimated number of successes (for the C-Pinterval)

f(1 - α/2,d f1,d f2)

1-α/2 quantile of the F distribution with d f1 and d f2 degrees of freedom