Table 2.
Significant risk factors associated with MCAT and the results of bias risk assessment
| Significant Risk Factors | No. of studies | No. of MC | No. of total patients | Analysis model | Adjusted OR (95%CI) | Study heterogeneity | Test for overall effect | Begg’s test P value | ||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Q | P | I2,% | Z | P value | ||||||||
| Preoperative patient condition-related risk factors | ||||||||||||
| Preoperative MC history | 12 | 377 | 2094 | Fixed | 4.13 [3.08, 5.54] | 13.46 | 0.26 | 18 | 9.46 | <0.00001 | 0.034 | |
| without | ref | |||||||||||
| with | ||||||||||||
| Preoperative bulbar symptoms | 8 | 254 | 1443 | Fixed | 3.71 [2.54, 5.42] | 7.55 | 0.37 | 7 | 6.76 | <0.00001 | 0.174 | |
| without | ref | |||||||||||
| with | ||||||||||||
| Preoperative Osserman stages | 10 | 358 | 2040 | Fixed | 4.55 [3.23, 6.13] | 30.74 | 0.0006 | 67 | 9.15 | <0.00001 | 0.64 | |
| I | ref | |||||||||||
| IIa + IIb + III + VI | 2 | 2.57 [1.43,4.61] | 0.01 | 0.94 | 0 | 3.16 | 0.002 | |||||
| IIb + III + VI | 8 | 11.15 [6.88,18.08] | 5.41 | 0.61 | 0 | 9.78 | <0.00001 | |||||
| VI + V | 1 | 1.80 [0.96, 3.36] | NA | NA | NA | 1.84 | 0.002 | |||||
| Postoperative lung infection | 5 | 92 | 448 | Fixed | 6.49 [2.64, 15.98] | 2.39 | 0.5 | 0 | 4.07 | <0.00001 | 0.624 | |
| without | ref | |||||||||||
| with | ||||||||||||
| Thymoma | 5 | 234 | 1390 | Fixed | 2.96 [2.13, 4.13] | 3.63 | 0.3 | 17 | 6.43 | <0.00001 | 0.806 | |
| no | ref | |||||||||||
| yes | ||||||||||||
| Preoperative dosage of pyridostigmine bromide | 4 | 193 | 1103 | Fixed | 3.53 [2.47,5.03] | 4.98 | 0.17 | 40 | 6.94 | <0.00001 | 1 | |
| ≥240 mg | ||||||||||||
| <240 mg | ref | |||||||||||
| Preoperative serum AchR-Ab level (nm/L) | 2 | 27 | 248 | Fixed | 8.74 [3.31, 23.08] | 0.03 | 0.87 | 0 | 3.65 | 0.0003 | 1 | |
| >100 | ||||||||||||
| ≤100 | ref | |||||||||||
| Operation time | 3 | 95 | 325 | Random | 1.18 [0.89, 1.57] | 19.47 | <0.00001 | 90 | 1.13 | 0.26 | 0.296 | |
| Surgery-related risk factors | ||||||||||||
| Intraoperative blood loss > 1000 ml | 2 | 26 | 185 | Fixed | 15.03 [3.50, 64.50] | 0.03 | 0.87 | 0 | 3.65 | 0.0003 | 1 | |
| >1000 ml | ||||||||||||
| ≤1000 ml | ref | |||||||||||
| WHO classification | 2 | 25 | 190 | Fixed | 15.23 [4.63, 50.13] | 0.22 | 0.64 | 0 | 4.48 | <0.00001 | 1 | |
| non-thymoma and non-invasive thymoma | ref | |||||||||||
| invasive thymoma | ||||||||||||
| Mode of operation | 4 | 66 | 252 | Fixed | 5.88 [2.06,16.80] | 2.09 | 0.55 | 0 | 3.3 | 0.001 | 0.089 | |
| video-assisted thoracoscopy | ref | |||||||||||
| thoracotomy | ||||||||||||
| Postoperative risk factors | ||||||||||||
| Preoperative lung function | 5 | 110 | 784 | Fixed | 5.71 [3.11, 10.48] | 3.3 | 0.51 | 0 | 5.62 | <0.00001 | 1 | |
| normal | ref | |||||||||||
| abnormal | ||||||||||||
| Major postoperative complications | 3 | 87 | 391 | Fixed | 33.78 [10.57,107.96] | 1.59 | 0.45 | 0 | 5.94 | <0.00001 | 1 | |
| without | ref | |||||||||||
| with | ||||||||||||
| Disease duration before thymectomy | 2 | 39 | 452 | Fixed | 5.45 [1.96, 15.14] | 0.02 | 0.9 | 0 | 3.26 | 0.001 | 1 | |
| 1983 | 11,345 | |||||||||||