Table 1. Characteristics of Individuals by Intensity of Lung Nodule Evaluation.
| Characteristic | Nodule evaluation, No. (%) | |||
|---|---|---|---|---|
| All patients (n = 5057) | Less intensive (n = 1863) | Guideline concordant (n = 1925) | More intensive (n = 1269) | |
| Age, y | ||||
| Median (IQR) | 67 (19) | 68 (20) | 68 (18) | 66 (18) |
| Mean (SD) | 67 (13) | 67 (14) | 67 (13) | 66 (13) |
| 35-44 | 284 (6) | 100 (5) | 106 (6) | 78 (6) |
| 45-54 | 693 (14) | 276 (15) | 222 (12) | 195 (15) |
| 55-64 | 1199 (24) | 418 (22) | 470 (24) | 311 (25) |
| 65-74 | 1427 (28) | 494 (27) | 574 (30) | 359 (28) |
| 75-84 | 1037 (21) | 374 (20) | 412 (21) | 251 (20) |
| ≥85 | 417 (8) | 201 (11) | 141 (7) | 75 (6) |
| Sex | ||||
| Female | 2786 (55) | 973 (52) | 1081 (56) | 732 (58) |
| Male | 2271 (45) | 890 (48) | 844 (44) | 537 (42) |
| Race/ethnicity | ||||
| White | 4597 (91) | 1692 (91) | 1764 (92) | 1141 (90) |
| Black | 110 (2) | 40 (2) | 42 (2) | 28 (2) |
| Asian | 203 (4) | 74 (4) | 66 (3) | 63 (5) |
| American Indian/Alaska Native | 23 (1) | 9 (1) | 7 (0.4) | 7 (1) |
| Native Hawaiian/Pacific Islander | 15 (0.3) | 7 (0.4) | 5 (0.3) | 3 (0.2) |
| Othera | 52 (1) | 22 (1) | 15 (1) | 15 (1) |
| Multiracial | 57 (1) | 19 (1) | 26 (1) | 12 (1) |
| Hispanic | ||||
| Yes | 126 (3) | 44 (2) | 51 (3) | 31 (2) |
| No | 4931 (98) | 1819 (98) | 1874 (97) | 1238 (98) |
| Smoking status | ||||
| Never | 2149 (42) | 609 (33) | 865 (45) | 675 (53) |
| Ever | 2908 (58) | 1254 (67) | 1060 (55) | 594 (47) |
| Comorbidity Index35 | ||||
| 0 | 2288 (45) | 830 (45) | 849 (44) | 609 (48) |
| 1 | 1334 (26) | 453 (24) | 548 (28) | 333 (26) |
| 2 | 635 (13) | 248 (13) | 249 (13) | 138 (11) |
| ≥3 | 800 (16) | 332 (18) | 279 (14) | 189 (15) |
| Frailty index36,37 | ||||
| Probability of frailty | ||||
| Median (IQR) | 0.06 (0.13) | 0.07 (0.15) | 0.07 (0.12) | 0.06 (0.11) |
| Mean (SD) | 0.12 (0.13) | 0.13 (0.15) | 0.11 (0.12) | 0.11 (0.13) |
| Frail | ||||
| Yes | 916 (18) | 393 (21) | 329 (17) | 194 (15) |
| No | 4141 (82) | 1470 (79) | 1596 (83) | 1075 (85) |
| Size of dominant nodule, mm | ||||
| Median (IQR) | 5.9 (5.0) | 6.0 (5.0) | 7.0 (8.0) | 4.5 (2.6) |
| Mean (SD) | 7.4 (5.4) | 7.5 (5.1) | 8.8 (6.4) | 5.0 (2.7) |
| ≤4 | 1694 (33) | 502 (27) | 568 (30) | 624 (49) |
| >4-6 | 1334 (26) | 555 (30) | 334 (17) | 445 (35) |
| >6-8 | 693 (14) | 264 (14) | 286 (15) | 143 (11) |
| >8 | 1336 (26) | 542 (29) | 737 (38) | 57 (5) |
| Multiple nodules | ||||
| Yes | 2766 (55) | 1001 (54) | 1101 (57) | 664 (52) |
| No | 2291 (45) | 862 (46) | 824 (43) | 605 (48) |
| Radiologist-recommended follow-up | ||||
| Yes | 3708 (73) | 1336 (72) | 1408 (73) | 964 (76) |
| No | 1349 (27) | 527 (28) | 517 (27) | 305 (24) |
| Infection suspected as a possible cause | ||||
| Yes | 125 (3) | 43 (2) | 58 (3) | 24 (2) |
| No | 4932 (98) | 1820 (98) | 1867 (97) | 1245 (98) |
| Health system | ||||
| A | 3220 (64) | 1106 (59) | 1286 (67) | 828 (65) |
| B | 1837 (36) | 757 (41) | 639 (33) | 441 (35) |
| Year of nodule detection | ||||
| 2005 | 251 (5) | 72 (4) | 95 (5) | 84 (7) |
| 2006 | 359 (7) | 110 (6) | 119 (6) | 130 (10) |
| 2007 | 388 (8) | 149 (8) | 121 (6) | 118 (9) |
| 2008 | 433 (9) | 167 (9) | 162 (8) | 104 (8) |
| 2009 | 441 (9) | 167 (9) | 176 (9) | 98 (8) |
| 2010 | 477 (9) | 194 (10) | 179 (9) | 104 (8) |
| 2011 | 476 (9) | 192 (10) | 195 (10) | 89 (7) |
| 2012 | 522 (10) | 201 (11) | 206 (11) | 115 (9) |
| 2013 | 522 (10) | 173 (9) | 200 (10) | 149 (12) |
| 2014 | 582 (12) | 204 (11) | 233 (12) | 145 (11) |
| 2015 | 606 (12) | 234 (13) | 239 (12) | 133 (10) |
| Fleischner Society guideline risk strata | ||||
| Low risk, mm nodule | ||||
| ≤4 | 779 (15) | 0 | 470 (24) | 309 (24) |
| >4-6 | 595 (12) | 276 (15) | 69 (4) | 250 (20) |
| >6-8 | 286 (6) | 108 (6) | 83 (4) | 95 (8) |
| >8 | 489 (10) | 225 (12) | 243 (13) | 21 (2) |
| High risk, mm nodule | ||||
| ≤4 | 915 (18) | 502 (27) | 98 (5) | 315 (25) |
| >4-6 | 739 (15) | 279 (15) | 265 (14) | 195 (15) |
| >6-8 | 407 (8) | 156 (8) | 203 (11) | 48 (4) |
| >8 | 847 (17) | 317 (17) | 494 (26) | 36 (3) |
Abbreviation: IQR, interquartile range.
a
Race/ethnicity was self-reported by patients; those who selected other did not indicate a specific race/ethnicity.