Table 2.
Concordance index corrected for optimism and index of prediction accuracy (IPA) for individual and combined predictive performance for each variable of the risk calculator predicting prostate cancer with Gleason ≥3 + 4 in 3616 men from the ERSPC.
| Univariable | Concordance Index (95% CI) | IPA (%) | Multivariable | Concordance Index (95% CI) | IPA (%) |
|---|---|---|---|---|---|
| PSA | 0.77 (0.74–0.80) | 15.4 | PSA + Age | 0.77 (0.74–0.80) | 15.5 |
| Age | 0.59 (0.56–0.62) | 0.7 | PSA + %FreePSA | 0.80 (0.77–0.83) | 20.3 |
| %FreePSA | 0.78 (0.75–0.81) | 11.1 | PSA + Age + %FreePSA | 0.81 (0.78–0.84) | 21.0 |
| DRE | 0.67 (0.64–0.70) | 3.9 | PSA + Age + DRE | 0.82 (0.79–0.84) | 22.3 |
| Prostate volume | 0.60 (0.56–0.63) | 0.7 | PSA + Age + DRE + %FreePSA | 0.84 (0.81–0.86) | 26.3 |
| FH | 0.51 (0.49–0.52) | 0.0 | PSA + Age + DRE + %FreePSA + PV | 0.86 (0.84–0.88) | 28.3 |
| IPSS/AUA | 0.52 (0.49–0.56) | 0.0 | Above + TRUS | 0.87 (0.85–0.90) | 31.6 |
| TRUS | 0.68 (0.65–0.71) | 4.5 | Above + FH and IPSS/AUA | 0.86 (0.84–0.88) | 31.6 |
%FreePSA = FreePSA divided by PSA, AUA = American Urological Association symptom score, PV = prostate volume, FH = family history.