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. 2019 Apr 25;2019(4):CD012663. doi: 10.1002/14651858.CD012663.pub2

11. Agreement analysis: number needed to biopsy.

Agreement analysis: number needed to biopsy by systematic biopsy to detect one extra prostate cancer not detected by the MRI‐pathway
Population Target
 condition NNBa
 (95% CI)
Biopsy status MRI
Biopsy‐naïve Positive G = 1 24 (15 to 40)
G ≥ 2 20 (12 to 36)
G ≥ 3 27 (16 to 45)
Negative G = 1 5 (4 to 7)
G ≥ 2 13 (9 to 18)
G ≥ 3 33 (18 to 63)
Prior‐negative biopsy Positive G = 1 33 (13 to 100)
G ≥ 2 37 (18 to 83)
G ≥ 3 83 (31 to 250)
Negative G = 1 7 (3 to 17)
G ≥ 2 19 (11 to 32)
G ≥ 3 31 (16 to 63)
CI: confidence interval; G: International Society of Urological Pathology grade; MRI: magnetic resonance imaging; MRI‐pathway: magnetic resonance imaging with or without magnetic resonance imaging‐targeted biopsy; N: number; NA: not applicable; NNB: number needed to biopsy; SBx: systematic biopsy

aNumber needed to biopsy by systematic biopsy is 100 divided by the added value of systematic biopsy.