Skip to main content
. Author manuscript; available in PMC: 2022 Jul 1.
Published in final edited form as: J Cardiovasc Comput Tomogr. 2020 Dec 28;15(4):333–338. doi: 10.1016/j.jcct.2020.12.008

Table 3:

Intraobserver, Interobserver and Scan-Rescan variability of per patient plaque volume measurements.

Intraobserver Variability Observation 1 Observation 2 LCC (95% CI) Mean difference P value Bland-Altman 95% LoA (95% CI) CoR
Total Plaque (mm3) 2063 ± 1246
[1443–2683]
2077 ± 1260
[1450–2704]
1.0
(1.0 – 1.0)
14.1 0.29 −93 (−155, −58)
to +121 (87, 183)
107.0
Non-calcified Plaque (mm3) 1765 ± 910
[1312–2217]
1780 ± 921
[1322–2238]
1.0
(1.0 – 1.0)
15.4 0.28 −99 (−165, −62)
to +129 (93, 196)
114.1
Calcified Plaque (mm3) 298 ± 425
[87–510]
297 ± 425
[86–508]
1.0
(1.0 – 1.0)
−1.2 0.68 −25 (−39, −17)
to +23 (15, 36)
23.7
Low-attenuation Plaque (mm3) 13 ± 13
[7–20]
12 ± 13
[5–18]
0.97
(0.93 – 0.99)
−1.6 0.02 −7 (−9, −5)
to +4 (1, 6)
5.2
Interobserver Variability Investigator 1 Investigator 2 LCC (95% CI) Mean difference P value Bland-Altman 95% LoA (95% CI) CoR
Total Plaque (mm3) 2063 ± 1246
[1443–2683]
1985 ± 1161
[1443–2683]
0.97
(0.93 – 0.99)
−74.2 0.24 −615 (−927, −442)
to +459 (286, 770)
537.0
Non-calcified Plaque (mm3) 1765 ± 910
[1312–2217]
1688 ± 803
[1289–2087]
0.95
(0.88 – 0.98)
−76.5 0.24 −594 (−894, −428)
to +441 (275, 742)
517.6
Calcified Plaque (mm3) 298 ± 425
[87–510]
297 ± 432
[82–512]
1.0
(0.99 – 1.0)
−1.7 0.84 −69 (−97, −41)
to 66 (38, 94)
67.5
Low-attenuation Plaque (mm3) 13 ± 13
[7–20]
14 ± 12
[8–20]
0.90
(0.76 – 0.96)
1.2 0.39 −10 (−14, −5)
to +12 (8, 17)
11.0
Scan-Rescan Variability Baseline Scan Repeat Scan LCC (95% CI) Mean difference P value Bland-Altman 95% LoA (95% CI) CoR
Total Plaque (mm3) 2063 ± 1246
[1443–2683]
2027 ± 1223
[1419–2635]
0.98
(0.94 – 0.99)
−35.6 0.56 −531 (−735, −328)
to 460 (257, 664)
495.7
Non-calcified Plaque (mm3) 1765 ± 910
[1312–2217]
1760 ± 928
[1299–2221]
0.97
(0.93 – 0.99)
−4.3 0.93 −418 (−587, −248)
to +409 (239, 579)
413.4
Calcified Plaque (mm3) 298 ± 425
[87–510]
267 ±377
[79–455]
0.96
(0.91 – 0.98)
−31.3 0.22 −237 (−321, −152)
to +174 (90, 258)
205.2
Low-attenuation Plaque (mm3) 13 ± 13
[7–20]
10 ±13
[4–17]
0.85
(0.64 – 0.94)
−2.6 0.11 −16 (−21, −10)
to +11 (5, 16)
13.1

Mean ± standard deviation [95% confidence interval], LCCC Lin’s concordance correlation coefficient (95% confidence interval), LoA – Limits of agreement (95% confidence interval), CoR - coefficient of repeatability.