Table 2.

Discrimination of PSA for predicting prostate cancer death compared with a pre-specified model containing age, total PSA and free PSA, and with the 4Kscore.

Age at blood draw	Subgroup by PSA	PSA centile	Total N	Prostate cancer deaths	C-index based on total PSA	C-index based on total and free PSA	C-index based on 4Kscore	Difference between 4Kscore and total PSA	Difference between 4Kscore and total and free PSA
50	All men	0	20524	36	0.859	0.722	0.819	−0.040	0.097
	PSA<1.0	<62	12598	5	0.635	0.598	0.581	−0.054	-0.017
	PSA≥1.0	≥62	7926	31	0.761	0.756	0.780	0.019	0.024
	PSA≥1.5	≥82	3662	23	0.735	0.779	0.788	0.053	0.009
	PSA≥2.0	≥90	1980	16	0.767	0.833	0.828	0.061	-0.004
	PSA≥3.0	≥96	714	10	0.881	0.875	0.877	−0.004	0.002
	PSA≥4.0	≥98	390	8	0.841	0.870	0.879	0.038	0.009
60	All men	0	18638	144	0.840	0.758	0.859	0.019	0.102
	PSA<1.0	<40	7367	9	0.630	0.603	0.530	−0.100	-0.074
	PSA≥1.0	≥40	11271	135	0.809	0.793	0.859	0.049	0.066
	PSA≥1.5	≥60	7493	123	0.785	0.807	0.860	0.076	0.053
	PSA≥2.0	≥71	5376	111	0.774	0.817	0.862	0.087	0.045
	PSA≥3.0	≥84	3057	86	0.811	0.833	0.881	0.070	0.048
	PSA≥4.0	≥90	1862	77	0.759	0.799	0.869	0.110	0.070