TABLE 2 Results of visual evaluation of nodules found on positron emission tomography/computed tomography (PET-CT), according to nodule and subject characteristics

	PET-CT	TN	FN	FP	TP	Sens %	Spec %	PPV %	NPV %	Accuracy %	p-value^#
Overall	378	164	70	21	123	64	89	85	70	76
Sex
Males	264	113	44	12	95	68	90	89	72	79
Females	114	51	26	9	28	52	85	76	66	69	0.05
Age years
<60	147	64	31	14	38	55	82	73	67	69
⩾60	231	100	39	7	85	69	93	92	72	80	0.02
Screening round
Baseline	148	81	11	7	49	82	92	88	88	88
2	57	17	11	3	26	70	85	90	61	75
3	62	19	28	3	12	30	86	80	40	50
4	44	10	10	4	20	67	71	83	50	68
5	47	31	6	4	6	50	89	60	84	79
6	20	6	4	0	10	71	100	100	60	80	<0.0001
Maximum nodule diameter mm
<10	145	75	40	4	26	39	95	87	65	70
10–15	104	51	19	4	30	61	93	88	73	78
⩾15	117	30	10	11	66	87	73	86	75	82	0.06
Nodule type
Solid	263	123	26	16	98	79	88	86	83	84
Partially solid	65	25	19	3	18	49	89	86	57	66
Nonsolid	48	15	25	1	7	22	94	88	38	46
Sub-solid^¶	113	40	44	4	25	36	91	86	48	58	<0.0001
Location: lobe
Lower	139	69	29	8	33	53	90	80	70	73
Upper	208	85	33	9	81	71	90	90	72	80
Other	30	10	8	3	9	53	77	75	56	63	0.09
Location: side
Left	148	64	27	8	49	64	89	86	70	76
Right	206	90	35	10	71	67	90	88	72	78	0.70
Nodule type and size mm
Sub-solid^¶ <10	40	17	19	0	4	17	100	100	47	53
Sub-solid^¶ 10–15	32	10	15	2	5	25	83	71	40	47
Sub-solid^¶ ⩾15	37	10	9	2	16	64	83	89	53	70
Solid <10	105	58	21	4	22	51	94	85	73	76
Solid 10–15	72	41	4	2	25	86	95	93	91	92
Solid ⩾15	80	20	1	9	50	98	69	85	95	88	<0.0001

Data are presented as n, unless otherwise stated. TN: true negative (negative PET for benign nodule); FN: false negative (negative PET for malignant nodule); FP: false positive (positive PET for benign nodule); TP: true positive (positive PET for malignant nodule); Sens: sensitivity; Spec: specificity; PPV: positive predictive value; NPV: negative predictive value. ^#: accuracy difference, Chi-squared test; ^¶: nonsolid+partially solid.