Table 2. Technical, epidemiological and anthropometric factors analyzed for evaluation of DNA yield variations.

Variables		N	%
Gender	Men	18680	39.6
	Women	28481	60.4
Age	<45	7054	15.0
	45–49	6631	14.1
	50–54	8835	18.7
	55–59	9514	20.1
	60–64	8567	18.2
	≥65	6560	13.9
Body Mass Index	Normal (<25)	14449	30.7
	Moderate pre-obesity (25–27.5)	12784	27.1
	Overweight (27.5–30)	7185	15.2
	Moderate obesity (30–35)	8953	19.0
	Obesity (≥35)	2934	6.2
	Missing	856	1.8
Cancer	Incidenta	10954	23.2
	Non Incident	36207	76.8
	Prevalentb	1311	2.8
	Non Prevalent	45850	97.2
Time from blood collection to incident cancer diagnosis	<2 years	1813	3.8
	2–5 years	3299	7.0
	5–10 years	4460	9.5
	≥10 years	1081	2.3
	Missing	36508	77.4
Time from prevalent cancer diagnosis to blood collection	<2 years	240	0.5
	2–5 years	298	0.6
	5–10 years	340	0.7
	≥10 years	427	0.9
	Missing	45856	97.3
	Never	21290	45.1
Tobacco consumption	Former	13847	29.4
	Current	11067	23.5
	Missing	957	2.0
Number of straws	1	11838	25.1
	2	35323	74.9
Extraction method	Extractor LS1	29441	62.4
	Extractor LS2	17305	36.7
	Manual	415	0.9
Quantification method	Nanodrop	33805	71.7
	Picogreen	13356	28.3
Haemolysis	Yes	3337	7.1
	No	21379	45.3
	Missing	22445	47.6
Haemolysis gradient	Light haemolysis	2870	6.08
	Medium haemolysis	445	0.94
	Heavy haemolysis	20	0.05
	Missing	43826	92.93
Time from collection to refrigeration	<5 min	2704	5.7
	5 min - 1 hour	5421	11.5
	1–3 hours	3934	8.3
	>3 hours	3987	8.5
	Missing	31115	66.0
Time from refrigeration to centrifugation	<1.5 hours	498	1.0
	1.5–2 hours	3482	7.4
	2–6 hours	2153	4.6
	≥6 hours	1865	4.0
	Missing	39163	83.0
Time from centrifugation to freezing	<45 min	6179	13.1
	45–59 min	6296	13.4
	1–2 hours	6800	14.4
	≥2 hours	7598	16.1
	Missing	20288	43.0

^aFirst incident cancer case.

^bLast prevalent cancer case.