Table 3. Pooled diagnostic accuracy of Scys in various AKI subgroup studies.
| Settings | AKI Pts/Total Pts; No. of studies | Sensitivity (95% CI) | Specificity (95% CI) | DOR (95% CI) | AUROC (95% CI) | I2 | Likelihood Ratio (95% CI) |
RDOR | P Value | |
|---|---|---|---|---|---|---|---|---|---|---|
| Positive | Negative | |||||||||
| Across all settings | 982/4247; 30 | 0.82 (0.75, 0.87) | 0.82 (0.78, 0.86) | 21 (12, 35) | 0.89 (0.86, 0.91) | 96 | 4.6 (3.6, 5.9) | 0.22 (0.16, 0.31) | ||
| Subgroups | ||||||||||
| 1.AKI setting: | ||||||||||
| CS-AKI | 189/586; 8 | 0.81 (0.71, 0.89) | 0.82 (0.72, 0.89) | 20 (7, 57) | 0.89 (0.86, 0.91) | 0 | 4.5 (2.7, 7.8) | 0.23 (0.13, 0.39) | 1.49 (0.65, 3.40) | 0.327 |
| ICU/CCU-AKI | 340/1194; 9 | 0.77 (0.66, 0.85) | 0.82 (0.72, 0.89) | 16 (6, 38) | 0.86 (0.83, 0.89) | 89 | 4.3 (2.5, 7.4) | 0.28 (0.18, 0.44) | ||
| CIN | 173/1253; 7 | 0.90 (0.61, 0.98) | 0.87 (0.82, 0.90) | 61(10, 388) | 0.90 (0.88, 0.93) | 95 | 6.7 (4.7, 9.7) | 0.11 (0.02, 0.57) | ||
| CIN | 173/1253; 7 | 0.90 (0.61, 0.98) | 0.87 (0.82, 0.90) | 61(10, 388) | 0.90 (0.88, 0.93) | 95 | 6.7 (4.7, 9.7) | 0.11 (0.02, 0.57) | 2.24 (0.65, 7.79) | 0.194 |
| Exp-CIN | 809/2994; 23 | 0.79 (0.74, 0.84) | 0.81 (0.75, 0.85) | 16(10, 26) | 0.87 (0.84, 0.89) | 85 | 4.1 (3.1, 5.4) | 0.26 (0.20, 0.34) | ||
| 2.AKI diagnostic criteria: | ||||||||||
| KDIGO | 206/866; 6 | 0.78 (0.49, 0.93) | 0.90 (0.81, 0.95) | 31 (6, 174) | 0.92 (0.90, 0.94) | 77 | 7.7 (3.4, 17.7) | 0.25 (0.09, 0.70) | 0.60 (0.29, 1.22) | 0.147 |
| AKIN ≥ 1 | 238/812; 8 | 0.81 (0.74, 0.86) | 0.81 (0.74, 0.87) | 18 (9, 35) | 0.86 (0.83, 0.89) | 0 | 4.3 (3.0, 6.4) | 0.24 (0.17, 0.34) | ||
| RIFLE ≥ R | 284/1241; 11 | 0.75 (0.67, 0.82) | 0.76 (0.67, 0.82) | 10 (5, 18) | 0.82 (0.72, 0.85) | 64 | 2.1 (2.2, 4.4) | 0.32 (0.23, 0.46) | ||
| 3.region: | ||||||||||
| Asia | 578/2197; 20 | 0.81 (0.73, 0.87) | 0.85 (0.80, 0.89) | 24 (12, 45) | 0.90 (0.87, 0.92) | 93 | 5.3 (3.8, 7.5) | 0.23 (0.15, 0.33) | 1.69 (0.60, 4.78) | 0.307 |
| Non-Asia | 404/2050; 10 | 0.83 (0.70, 0.91) | 0.78 (0.71, 0.83) | 17 (7, 43) | 0.85 (0.82, 0.88) | 82 | 3.7 (2.7, 5.2) | 0.22 (0.11, 0.42) | ||
| 4.Scys assay: | ||||||||||
| PETIA | 129/546; 5 | 0.76 (0.51, 0.91) | 0.87 (0.74, 0.94) | 21 (4, 103) | 0.90 (0.87, 0.92) | 88 | 5.8 (2.5, 13.5) | 0.27 (0.11, 0.67) | 1.21 (0.56, 2.60) | 0.614 |
| PENIA | 484/2043; 14 | 0.82 (0.31, 0.81) | 0.78 (0.72, 0.83) | 16 (8, 31) | 0.86 (0.83, 0.89) | 62 | 3.8 (2.8, 5.0) | 0.24 (0.15, 0.37) | ||
| ELISA | 282/1121; 8 | 0.77 (0.66, 0.85) | 0.86 (0.77, 0.92) | 21 (8, 55) | 0.88 (0.85, 0.90) | 72 | 5.6 (3.0, 10.3) | 0.27 (0.17, 0.42) | ||
| 5.participant mean age: | ||||||||||
| ≤60 years | 445/1928; 12 | 0.85 (0.75, 0.91) | 0.82 (0.74, 0.88) | 26 (11, 61) | 0.90 (0.87, 0.93) | 89 | 4.8 (3.1, 7.4) | 0.19 (0.11, 0.33) | 1.24 (0.43, 1.56) | 0.684 |
| >60 years | 451/1994; 15 | 0.80 (0.70, 0.88) | 0.82 (0.76, 0.88) | 18 (9, 36) | 0.88 (0.84, 0.90) | 93 | 4.4 (3.2, 5.9) | 0.24 (0.15, 0.38) | ||
| 6.male rate: | ||||||||||
| ≤70% | 604/2512; 14 | 0.78 (0.67, 0.86) | 0.83 (0.78, 0.88) | 18 (9, 36) | 0.88 (0.85, 0.91) | 94 | 4.7 (3.4, 6.5) | 0.26 (0.17, 0.41) | 0.96 (0.37, 2.49) | 0.925 |
| >70% | 349/1603; 15 | 0.83 (0.75, 0.90) | 0.80 (0.73, 0.85) | 20 (10, 41) | 0.88 (0.85, 0.91) | 77 | 4.1 (3.0, 5.7) | 0.21 (0.13, 0.33) | ||
| 7.sample size: | ||||||||||
| ≤100 | 488/1598; 20 | 0.82 (0.74, 0.88) | 0.81 (0.77, 0.85) | 20 (10, 39) | 0.88 (0.85, 0.91) | 42 | 4.4 (3.3, 5.8) | 0.22 (0.14, 0.33) | 0.59 (0.21, 1.65) | 0.304 |
| >100 | 494/2649; 10 | 0.81 (0.67, 0.89) | 0.85 (0.76, 0.91) | 23 (10, 54) | 0.90 (0.87, 0.92) | 96 | 5.3 (3.3, 8.6) | 0.23 (0.13, 0.40) | ||
Abbreviations: AKI, acute kidney injury; AUROC, the area under the receiver operating characteristic curve; CCU, coronary care unit; CIN, contrast-induced nephropathy; CS, cardiac surgery; DOR, diagnostic odd ratio; ELISA, enzyme-linked immunosorbent assay; KDIGO, Kidney Disease: Improving Global Outcomes; PENIA, particle-enhanced nephelometric immunoassay; PETIA, particle-enhanced turbidimetric immunoassay; Pts, patients; RIFLE, risk-injury-failure-loss-end stage renal disease; Scr, serum creatinine; Scys, serum cystatin C.