Table 2.
The rule-out value of individual and combinations of blood investigations for myeloma
| Investigations | Blood test results | Sensitivity, % (95% CI) | Specificity, % (95% CI) | LR- (95% CI) | ||||
|---|---|---|---|---|---|---|---|---|
|
| ||||||||
| Number tested,an | True positive | False positive | False negative | True negative | ||||
| Individual tests | ||||||||
| ESR | 2192 | 844 | 546 | 154 | 648 | 85 (82 to 87) | 54 (51 to 57) | 0.28 (0.24 to 0.33) |
| PV | 433 | 162 | 95 | 39 | 137 | 81 (74 to 86) | 59 (52 to 64) | 0.32 (0.24 to 0.44) |
| Hb | 5934 | 1243 | 912 | 596 | 3183 | 68 (65 to 70) | 78 (76 to 79) | 0.42 (0.39 to 0.45) |
| CAL | 2809 | 246 | 43 | 893 | 1627 | 22 (19 to 24) | 98 (97 to 0.98) | 0.81 (0.78 to 0.83)b |
| CREAT | 7407 | 648 | 1021 | 1202 | 4536 | 35 (33 to 37) | 82 (81 to 83) | 0.80 (0.77 to 0.83)b |
| CRP | 1274 | 316 | 281 | 319 | 358 | 46 (42 to 50) | 63 (59 to 67) | 0.87 (0.78 to 0.94)b |
|
| ||||||||
| Combinations (two tests) | ||||||||
| Hb and PV | 396 | 175 | 119 | 10 | 92 | 95 (90 to 97) | 44 (37 to 50) | 0.12 (0.07 to 0.23)c |
| Hb and ESR | 2071 | 884 | 603 | 72 | 512 | 93 (91 to 94) | 46 (43 to 49) | 0.16 (0.13 to 0.21)c |
| Hb and CRP | 1193 | 491 | 311 | 111 | 280 | 84 (80 to 86) | 47 (43 to 52) | 0.39 (0.32 to 0.47) |
|
| ||||||||
| Combinations (three tests) | ||||||||
| Hb, CREAT, and PV | 356 | 165 | 111 | 6 | 74 | 97 (93 to 99) | 40 (33 to 47) | 0.09 (0.04 to 0.20)c |
| Hb, CAL, and PV | 213 | 128 | 49 | 3 | 33 | 98 (94 to 100) | 40 (30 to 52) | 0.06 (0.02 to 0.18)c |
| Hb, CREAT, and ESR | 1864 | 823 | 599 | 54 | 388 | 94 (92 to 95) | 39 (36 to 42) | 0.16 (0.12 to 0.21)c |
| Hb, CAL, and ESR | 1146 | 590 | 286 | 45 | 225 | 93 (91 to 95) | 44 (40 to 49) | 0.16 (0.12 to 0.22)c |
| Hb, CREAT, and CRP | 1115 | 505 | 341 | 70 | 199 | 88 (85 to 90) | 37 (33 to 41) | 0.33 (0.26 to 0.42) |
| Hb, CAL, and CRP | 722 | 363 | 160 | 64 | 135 | 85 (81 to 88) | 46 (40 to 52) | 0.33 (0.25 to 0.42) |
|
| ||||||||
| Combinations (four tests) | ||||||||
| Hb, CAL, CREAT, and PV | 211 | 127 | 50 | 3 | 31 | 98 (93 to 100) | 38 (28 to 50) | 0.06 (0.02 to 0.19)c |
| Hb, CAL, CREAT, and ESR | 1103 | 569 | 309 | 39 | 186 | 94 (91 to 95) | 38 (33 to 42) | 0.17 (0.12 to 0.24)c |
| Hb, CAL, CREAT, and CRP | 706 | 373 | 189 | 44 | 100 | 89 (86 to 92) | 35 (29 to 40) | 0.31 (0.22 to 0.42) |
a
Sample size corresponds to the number of patients who had the test or a particular combination of tests.
b
NRL = negative likelihood ratio (LR−) >0.8.
c
NRL ≤0.2. CAL = calcium. CREAT = creatinine. CRP = C-reactive protein. ESR = erythrocyte sedimentation rate. Hb = haemoglobin. LR− = negative likelihood ratio. PV = plasma viscosity.