Table 2. The primary outcomes in subgroups after CXL treatment. The 1-, 3-, 6- and 12-month CXL results are shown. UCVA = uncorrected visual acuity, BCVA = best-corrected visual acuity, MRSE = mean refractive spherical equivalent, Kmax = steepest simulated keratometry, Kave = average simulated keratometry, CCT = central corneal thickness.
| Group | Main Outcome | No. of Studies | No. of Eyes | Effect Size SMD (95% CI) | Heterogeneity (I2; p-value) | Test for Overall Effect (Z, p-value) |
|---|---|---|---|---|---|---|
| Post-CXL-1m | UCVA | 7 | 374 | 0.13 (−0.09, 0.36) | 51%; 0.06 | 1.14; 0.26 |
| BCVA | 7 | 374 | −0.05 (−0.32, 0.22) | 66%; 0.007 | 1.35; 0.18 | |
| MRSE | 3 | 150 | −0.14 (−0.37, 0.09) | 37%; 0.23 | 0.89; 0.37 | |
| Astigmatism | 4 | 292 | −0.11 (−0.28, 0.05) | 13%; 0.33 | 1.34; 0.18 | |
| Kmax | 3 | 231 | 0.04 (−0.15, 0.22) | 0%; 0.47 | 0.38; 0.7 | |
| Kave | 4 | 275 | 0.04 (−0.13, 0.21) | 0%; 0.72 | 0.48; 0.63 | |
| CCT | 4 | 297 | 0.24 (0.08, 0.41) | 84%; 0.0003 | 2.93; 0.003* | |
| Post-CXL-3m | UCVA | 7 | 374 | 0.37 (0.22, 0.52) | 68%; 0.005 | 4.80; <0.00001* |
| BCVA | 7 | 374 | 0.41 (0.26, 0.56) | 79%; <0.0001 | 2.53; <0.00001* | |
| MRSE | 3 | 150 | −0.16 (−0.41, 0.09) | 0%; 0.76 | 1.24; 0.22 | |
| Astigmatism | 4 | 292 | 0.00 (−0.17, 0.17) | 6%; 0.37 | 0.05; 0.96 | |
| Kmax | 3 | 231 | 0.14 (−0.04, 0.33) | 15%; 0.31 | 1.54; 0.12 | |
| Kave | 4 | 275 | 0.22 (0.05, 0.39) | 6%; 0.36 | 2.54; 0.01* | |
| CCT | 4 | 297 | 0.16 (−0.01, 0.33) | 81%; 0.001 | 1.43; 015 | |
| Post-CXL-6m | UCVA | 11 | 442 | 0.49 (0.18, 0.8) | 75%; <0.0001 | 3.07; 0.002* |
| BCVA | 11 | 442 | 0.72 (0.17, 1.28) | 91%; <0.00001 | 2.56; 0.01* | |
| MRSE | 6 | 203 | −0.55 (−1.09, −0.02) | 83%; <0.0001 | 2.02; 0.04* | |
| Astigmatism | 7 | 346 | −0.04 (−0.25, 0.17) | 31%; 0.19 | 0.37; 0.71 | |
| Kmax | 7 | 321 | 0.15 (−0.01, 0.32) | 0%; 0.98 | 1.84; 0.07 | |
| Kave | 8 | 352 | 0.19 (0.04, 0.35) | 0%; 0.75 | 2.42; 0.02* | |
| CCT | 8 | 373 | 0.38 (0.16, 0.60) | 41%; 0.11 | 3.40; 0.0007* | |
| Post-CXL-12m | UCVA | 13 | 585 | 0.52(0.25, 0.78) | 75%; <0.0001 | 3.83; 0.0001* |
| BCVA | 14 | 638 | 0.81 (0.43, 1.18) | 89%; <0.0001 | 4.19; <0.00001* | |
| MRSE | 8 | 334 | −0.27(−0.42, −0.11) | 0%; 1 | 3.42; <0.001* | |
| Astigmatism | 9 | 487 | 0.23(0.1, 0.37) | 33%; 0.16 | 3.42; <0.001* | |
| Kmax | 12 | 487 | 0.15 (0.02, 0.28) | 0%; 0.99 | 2.21; 0.03* | |
| Kave | 13 | 598 | 0.19 (0.07, 0.31) | 0%; 0.81 | 3.06; 0.02* | |
| CCT | 11 | 536 | 0.32 (0.19, 0.44) | 68%; 0.0003 | 4.82; <0.00001* | |
| Front elevation | 4 | 98 | −0.1 (−0.39, 0.18) | 43% 0.16 | 0.72; 0.47 | |
| Back elevation | 5 | 123 | 0.31 (−0.46, 1.09) | 88%; <0.0001 | 0.79; 0.43 | |
| ECD | 3 | 72 | 0.1(−0.23, 0.43) | 0%; 0.9 | 0.6; 0.55 |