Table 1.

Number of PSMs obtained by Strategy1 according to raw SPC

Min raw SPC	$\mathrm{\Delta }m$ = 0		$\mathrm{\Delta }m<0$		$\mathrm{\Delta }m>0$		Total
	#target	#decoy	#target	#decoy	#target	#decoy	#target	#decoy	FDR(%)
7	71,852	87,705	88,895	39,432	107,842	59,678	268,589	186,815	41.02
8	71,852	87,705	55,874	12,352	61,225	19,550	188,951	119,607	38.76
9	32,972	32,740	41,378	3874	40,085	4822	114,435	41,436	26.58
10	32,970	32,739	31,973	868	30,245	1026	95,188	34,633	26.68
11	10,918	11,209	26,095	310	24,547	305	61,560	11,824	16.11
12	10,918	11,208	21,553	112	20,313	94	52,784	11,414	17.78
13	2571	1180	17,893	46	16,939	34	37,403	1260	3.26
14	2571	1180	14,955	22	14,243	17	31,769	1219	3.7
15	1137	380	12,352	9	11,818	9	25,307	398	1.55
16	1137	380	10,239	6	9801	5	21,177	391	1.81
17	672	61	8403	5	8085	4	17,160	70	0.41
18	672	61	6907	4	6662	3	14,241	68	0.48
19	495	49	5590	2	5413	1	11,498	52	0.45
20	495	49	4557	1	4415	1	9467	51	0.54

The best PSMs provided by SpecOMS are separated into three groups based on $\mathrm{\Delta }m$, and subdivided in each group by the origin of the hit (target or decoy database). An FDR < 1% is reached whenever raw SPC is greater than or equal to 17 (row in bold)