Table 2.
Pooled summary results by subgroups
| Subgroups | No of studies | Sensitivity (95% CI) | Sensitivity with I2, % | Specificity (95% CI) | Specificity with I2, % |
| Total | 25 | 68 (61 to 74) | 86.9% | 57 (50 to 65) | 86.9 |
| Age | |||||
| ≤40 years | 4 | 71 (54 to 84) | 53.1% | 79 (39 to 96) | 70.1 |
| >40 years | 21 | 68 (60 to 75) | 87.4% | 57 (49 to 64) | 87.4 |
| AVS procedure | |||||
| With ACTH | 17 | 66 (57 to 73) | 86.5% | 56 (46 to 65) | 90.5 |
| Without ACTH | 7 | 70 (58 to 79) | 90.3% | 60 (45 to 74) | 79.2 |
| Cutoff values of LI | |||||
| LI≥2 | 4 | 61 (37 to 80) | 95.5% | 54 (38 to 68) | 88.3 |
| LI≥4 | 18 | 69 (62 to 75) | 76.4% | 59 (50 to 68) | 89.0 |
| Screening test for PA | |||||
| ARR | 21 | 66 (58 to 72) | 87.7% | 58 (50 to 65) | 86.2 |
| Not ARR | 4 | 78 (69 to 84) | 0% | 59 (29 to 84) | 89.1 |
| Confirmatory test for PA | |||||
| Salt-loading test | 12 | 71 (62 to 80) | 78.6% | 60 (49 to 70) | 74.9 |
| Additional options | 8 | 57 (46 to 67) | 90.6% | 66 (60 to 72) | 66 |
| No | 5 | 72 (64 to 79) | 55.8% | 42 (24 to 63) | 90.3 |
| Imaging methodology | |||||
| CT | 20 | 67 (59 to 74) | 88.6% | 60 (53 to 67) | 82.5 |
| Contrast CT | 8 | 77 (66 to 85) | 86.4% | 60 (49 to 69) | 82.2 |
| Nocontrast CT | 12 | 58 (49 to 66) | 83.8% | 60 (51 to 68) | 81.8 |
| CT/MRI | 5 | 69 (62 to 76) | 30% | 45 (27 to 64) | 87.9 |
| Quality of studies | |||||
| High-quality studies | 13 | 78 (73 to 83) | 48.6% | 51 (39 to 63) | 78.6 |
| Unclear-quality studies | 6 | 62 (58 to 65) | 0% | 62 (54 to 70) | 85.1 |
| Low-quality studies | 6 | 44 (38 to 50) | 46.4% | 69 (60 to 78) | 69.2 |
| Sample size | |||||
| ≥100 | 10 | 59 (51 to 67) | 90.6% | 58 (49 to 66) | 92.1 |
| <100 | 15 | 74 (67 to 81) | 71.3% | 60 (47 to 71) | 78.1 |
| Outlier excluded | 20 | 65 (60 to 70) | 77.1% | 59 (52 to 66) | 85.2 |
ACTH, adrenocorticotropic hormone; ARR, aldosterone-to-renin ratio; AVS, adrenal vein sampling; LI, lateralisation index; PA, primary aldosteronism.