Table 2.
The main, subgroup and sensitivity analyses
| Subgroup | No. of studies | Sample size | B versus non-B | O versus non-O | A versus non-A | AB versus non-AB | ||||
| RR (95% CI) | P value | RR (95% CI) | P value | RR (95% CI) | P value | RR (95% CI) | P value | |||
| All studies | 38 | 6 487 481 | 0.92 (0.86 to 0.98) | 0.007 | 1.07 (0.99 to 1.15) | 0.082 | 1.01 (0.96 to 1.07) | 0.728 | 1.04 (0.95 to 1.13) | 0.419 |
| HBV prevalence | ||||||||||
| Higher endemic areas (≥5%) | 14 | 3 983 732 | 0.90 (0.83 to 0.98) | 0.013 | 1.12 (1.01 to 1.24) | 0.025 | 0.99 (0.91 to 1.08) | 0.82 | 1.00 (0.89 to 1.14) | 0.962 |
| Lower endemic areas (<5%) | 24 | 2 503 749 | 0.93 (0.85 to 1.02) | 0.126 | 1.03 (0.93 to 1.15) | 0.566 | 1.03 (0.95 to 1.11) | 0.471 | 1.06 (0.95 to 1.18) | 0.292 |
| Race | ||||||||||
| Caucasian | 23 | 2 488 675 | 0.96 (0.87 to 1.05) | 0.386 | 1.04 (0.94 to 1.16) | 0.465 | 1.03 (0.94 to 1.13) | 0.472 | 1.05 (0.93 to 1.18) | 0.461 |
| Asian | 7 | 3 920 902 | 0.91 (0.86 to 0.97) | 0.003 | 1.10 (0.99 to 1.22) | 0.075 | 0.98 (0.97 to 0.99) | <0.001 | 0.96 (0.87 to 1.06) | 0.451 |
| African | 8 | 77 904 | 0.78 (0.58 to 1.05) | 0.099 | 1.04 (0.77 to 1.40) | 0.803 | 0.99 (0.73 to 1.33) | 0.919 | 1.02 (0.62 to 1.67) | 0.953 |
| Sample size | ||||||||||
| ≥2000 | 24 | 6 475 196 | 0.93 (0.87 to 0.99) | 0.018 | 1.07 (0.98 to 1.16) | 0.135 | 0.99 (0.94 to 1.05) | 0.795 | 1.00 (0.92 to 1.08) | 0.914 |
| <2000 | 14 | 12 285 | 0.85 (0.64 to 1.13) | 0.275 | 1.08 (0.90 to 1.29) | 0.398 | 1.07 (0.85 to 1.33) | 0.577 | 1.20 (0.89 to 1.61) | 0.238 |
| Population | ||||||||||
| General | 6 | 3 910 128 | 0.93 (0.87 to 0.99) | 0.016 | 1.07 (0.99 to 1.15) | 0.078 | 0.98 (0.96 to 1.00) | 0.035 | 0.89 (0.88 to 0.90) | <0.001 |
| Blood donors | 29 | 2 574 698 | 0.89 (0.81 to 0.97) | 0.011 | 1.08 (0.97 to 1.20) | 0.154 | 1.01 (0.92 to 1.10) | 0.885 | 1.08 (0.95 to 1.23) | 0.248 |
| Patients | 3 | 2655 | 0.92 (0.71 to 1.19) | 0.517 | 1.04 (0.71 to 1.54) | 0.828 | 1.09 (0.91 to 1.30) | 0.345 | 1.17 (0.94 to 1.46) | 0.169 |
| Income group | ||||||||||
| High | 7 | 148 804 | 0.96 (0.91 to 1.00) | 0.065 | 1.17 (0.95 to 1.44) | 0.135 | 0.91 (0.74 to 1.11) | 0.343 | 0.97 (0.84 to 1.13) | 0.712 |
| Upper middle | 9 | 6 101 344 | 1.01 (0.88 to 1.15) | 0.927 | 0.97 (0.82 to 1.15) | 0.756 | 1.00 (0.96 to 1.06) | 0.791 | 1.02 (0.88 to 1.17) | 0.814 |
| Lower middle | 18 | 214 587 | 0.86 (0.76 to 0.97) | 0.011 | 1.03 (0.93 to 1.13) | 0.582 | 1.13 (1.01 to 1.25) | 0.03 | 1.13 (0.95 to 1.34) | 0.173 |
| Low | 4 | 22 746 | 0.88 (0.56 to 1.38) | 0.572 | 1.34 0.72 to 2.48) | 0.353 | 0.71 (0.42 to 1.21) | 0.209 | 0.84 (0.43 to 1.64) | 0.613 |
| Study design | ||||||||||
| Cross-sectional | 37 | 6 408 776 | 0.91 (0.85 to 0.97) | 0.007 | 1.07 (0.98 to 1.17) | 0.111 | 1.01 (0.95 to 1.08) | 0.78 | 1.06 (0.96 to 1.17) | 0.244 |
| Cohort | 1 | 78 705 | 0.96 (0.92 to 1.01) | 0.098 | 1.05 (1.01 to 1.10) | 0.016 | 1.00 (0.95 to 1.05) | 0.957 | 0.92 (0.84 to 1.00) | 0.053 |
| Publication year | ||||||||||
| Before 2010 | 17 | 123 268 | 0.80 (0.67 to 0.96) | 0.015 | 1.12 (0.97 to 1.29) | 0.112 | 1.02 (0.85 to 1.22) | 0.83 | 1.22 (1.01 to 1.46) | 0.04 |
| After 2010 | 21 | 6 364 213 | 0.95 (0.88 to 1.01) | 0.106 | 1.05 (0.95 to 1.15) | 0.335 | 1.00 (0.94 to 1.06) | 0.91 | 0.98 (0.89 to 1.07) | 0.627 |
| Sensitive analyses | ||||||||||
| Removed Liu’s study17 | 37 | 2 660 356 | 0.91 (0.85 to 0.98) | 0.012 | 1.06 (0.98 to 1.15) | 0.138 | 1.01 (0.94 to 1.08) | 0.816 | 1.06 (0.97 to 1.17) | 0.213 |
| Removed Mohammedali’s study18 | 37 | 4 459 413 | 0.91 (0.85 to 0.97) | 0.002 | 1.08 (1.00 to 1.16) | 0.044 | 1.01 (0.94 to 1.07) | 0.857 | 1.04 (0.95 to 1.14) | 0.445 |
| Removed both Liu’s and Mohammedali’s study17 18 | 36 | 632 288 | 0.90 (0.83 to 0.97) | 0.007 | 1.07 (0.98 to 1.17) | 0.115 | 1.00 (0.92 to 1.09) | 0.946 | 1.08 (0.96 to 1.20) | 0.211 |
HBV, Hepatitis B virus; RR, risk ratio.