Nomogram 1
Parameters for Model 1:
(1) age
(2) digital rectal examination (DRE)
(3) PSA
(4) fraction of free PSA
points for age =
= (0.2776 * (age in years)) - 2.7768
|
Digital Rectal Exam
|
Points
|
|
normal
|
0
|
|
suspicious for cancer
|
20.9
|
points for serum PSA =
= (0.337 * (serum PSA))
points for free PSA =
= (-100 * (decimal fraction of free PSA)) + 100
total score 1 =
= (points for age) + (points for DRE) + (points for PSA) + (points for fraction of free PSA)
X =
= (0.08709 * (total score 1)) - 9.432
probability of prostate cancer on the needle biopsy =
= 1 / (1 + EXP((-1) * X))
Nomogram 2
Parameters for Model 2:
(1) age
(2) digital rectal examination (DRE)
(3) serum PSA
points for age =
= (0.699 * (age in years)) - 19.02
|
Digital Rectal Exam
|
Points
|
|
normal
|
0
|
|
suspicious for cancer
|
45
|
points for PSA =
= (PSA) * 2
total score 2 =
= (points for age) + (points for DRE) + (points for PSA)
Y =
= (0.02794 * (total score 2)) - 2.386
probability of prostate cancer on the needle biopsy =
= 1 / (1 + EXP((-1) * Y))
