Table 6. Meta-regression analysis for the main potential interference factors.
| Models | Factors | P | Coefficients (exponentiated form) | 95% CI | T2 | R2 (%) |
|---|---|---|---|---|---|---|
| Recessive (1F-1F vs. 1F-1S+1S-1S) | Publication year | 0.121 | 0.953 | 0.893-1.018 | 0 | 100.00 |
| Sample size | 0.447 | 0.999 | 0.994-1.003 | 0.06 | 29.05 | |
| Quality of study | 0.426 | 0.653 | 0.184-2.315 | 0.07 | 18.14 | |
| Country | 0.101 | 0.850 | 0.690-1.047 | 0 | 100.00 | |
| HWE | 0.719 | 1.658 | 0.055-50.393 | 0.09 | −1.86 | |
| Ethnicity | 0.766 | 1.229 | 0.228-6.610 | 0.10 | −13.80 | |
| Genotyping method | 0.468 | 0.566 | 0.088-3.645 | 0.09 | −1.77 | |
| Diagnostic criteria | 0.468 | 0.566 | 0.09-3.65 | 0.09 | −1.77 | |
| Co-dominant (1F-1F vs. 2-2) | Publication year | 0.602 | 0.578 | 0.784-1.170 | 1.68 | −15.57 |
| Sample size | 0.313 | 0.996 | 0.9985-1.006 | 1.37 | 5.69 | |
| Quality of study | 0.955 | 1.077 | 0.043-26.893 | 1.83 | −25.68 | |
| Country | 0.013 | 0.568 | 0.388-0.833 | 0.13 | 91.26 | |
| HWE | 0.495 | 0.144 | 0.000-127.537 | 1.70 | −16.93 | |
| Ethnicity | 0.544 | 0.411 | 0.012-13.874 | 1.80 | −23.21 | |
| Genotyping method | 0.861 | 0.735 | 0.010-54.324 | 1.85 | −26.86 | |
| Diagnostic criteria | 0.861 | 0.73 | 0.01-54.32 | 1.85 | −26.86 | |
| Co-dominant (1F-2 vs. 2-2) | Publication year | 0.498 | 1.040 | 0.910-1.188 | 0.64 | −46.21 |
| Sample size | 0.043 | 0.995 | 0.990-1.000 | 0 | 100.00 | |
| Quality of study | 0.544 | 1.655 | 0.244-11.223 | 0.51 | −15.50 | |
| Country | 0.022 | 0.685 | 0.507-0.927 | 0 | 100.00 | |
| HWE | 0.505 | 0.330 | 0.007-15.061 | 0.55 | −25.11 | |
| Ethnicity | 0.270 | 0.397 | 0.062-2.545 | 0.38 | 12.78 | |
| Genotyping method | 0.257 | 3.772 | 0.281-50.618 | 0.45 | −1.67 | |
| Diagnostic criteria | 0.257 | 3.772 | 0.281-50.618 | 0.45 | −1.67 | |
| Co-dominant (1F-1F vs. 1F-2) | Publication year | 0.154 | 0.930 | 0.832-1.040 | 0.26 | 35.41 |
| Sample size | 0.942 | 1.000 | 0.993-1.007 | 0.53 | −31.14 | |
| Quality of study | 0.351 | 0.483 | 0.079-2.973 | 0.37 | 10.24 | |
| Country | 0.048 | 0.777 | 0.60-0.99 | 0 | 100.00 | |
| HWE | 0.960 | 0.907 | 0.008-106.500 | 0.50 | −22.89 | |
| Ethnicity | 0.468 | 2.107 | 0.184-24.153 | 0.39 | 5.40 | |
| Genotyping method | 0.186 | 0.192 | 0.012-3.064 | 0.32 | 21.56 | |
| Diagnostic criteria | 0.186 | 0.192 | 0.012-3.064 | 0.32 | 21.56 | |
| Dominant (2-2+1S-2 vs. 1S-1S) | Publication year | 0.195 | 1.024 | 0.984-1.067 | 0 | 100.00 |
| Sample size | 0.872 | 1.000 | 0.996-1.003 | 0.05 | −265.50 | |
| Quality of study | 0.462 | 1.417 | 0.479-4.196 | 0.01 | −4.41 | |
| Country | 0.308 | 1.143 | 0.852-1.536 | 0.11 | −757.84 | |
| HWE | 0.882 | 1.129 | 0.167-7.607 | 0.07 | −444.37 | |
| Ethnicity | 0.693 | 0.837 | 0.293-2.393 | 0.03 | −101.06 | |
| Genotyping method | 0.223 | 1.550 | 0.704-3.411 | 0 | 100.00 | |
| Diagnostic criteria | 0.223 | 1.550 | 0.704-3.411 | 0 | 100.00 | |
| Recessive(2-2 vs. 1S-2+1S-1S) | Publication year | 0.985 | 1.001 | 0.879-1.140 | 0.86 | −36.82 |
| Sample size | 0.166 | 1.004 | 0.998-1.01 | 0.85 | 12.73 | |
| Quality of study | 0.612 | 0.661 | 0.100-4.393 | 0.78 | −24.50 | |
| Country | 0.015 | 1.503 | 1.121-2.017 | 0.07 | 88.66 | |
| HWE | 0.415 | 3.823 | 0.090-162.648 | 0.73 | −16.10 | |
| Ethnicity | 0.343 | 2.174 | 0.343-13.773 | 0.73 | −16.74 | |
| Genotyping method | 0.736 | 0.679 | 0.046-9.990 | 0.85 | −36.14 | |
| Diagnostic criteria | 0.736 | 0.679 | 0.046-9.990 | 0.85 | −36.14 | |
| Co-dominant (2-2 vs. 1S-1S) | Publication year | 0.833 | 1.013 | 0.879-1.167 | 0.99 | −45.10 |
| Sample size | 0.345 | 1.003 | 0.996-1.011 | 0.82 | −19.99 | |
| Quality of study | 0.986 | 1.017 | 0.110-9.406 | 0.95 | −39.55 | |
| Country | 0.036 | 1.558 | 1.041-2.333 | 0.22 | 68.10 | |
| HWE | 0.614 | 2.546 | 0.034-187.950 | 0.93 | −36.16 | |
| Ethnicity | 0.605 | 1.617 | 0.187-13.981 | 0.95 | −40.12 | |
| Genotyping method | 0.991 | 0.985 | 0.051-18.87 | 1.03 | −51.35 | |
| Diagnostic criteria | 0.991 | 0.985 | 0.051-18.87 | 1.03 | −51.35 | |
| Co-dominant (2-2 vs. 1S-2) | Publication year | 0.849 | 0.990 | 0.870-1.125 | 0.80 | −40.95 |
| Sample size | 0.112 | 1.004 | 0.999-1.010 | 0.42 | 25.98 | |
| Quality of study | 0.452 | 0.547 | 0.087-3.433 | 0.68 | −19.59 | |
| Country | 0.012 | 1.481 | 1.133-1.936 | 0 | 100.00 | |
| HWE | 0.372 | 4.254 | 0.108-167.491 | 0.66 | −15.97 | |
| Ethnicity | 0.254 | 2.503 | 0.422-14.831 | 0.63 | −10.25 | |
| Genotyping method | 0.542 | 0.503 | 0.037-6.784 | 0.75 | −32.43 | |
| Diagnostic criteria | 0.542 | 0.503 | 0.037-6.784 | 0.75 | −32.43 | |
| 1S vs. 2 | Publication year | 0.424 | 0.984 | 0.941-1.030 | 0.08 | 0.93 |
| Sample size | 0.819 | 1.000 | 0.997-1.002 | 0.11 | −28.57 | |
| Quality of study | 0.805 | 0.927 | 0.451-1.905 | 0.11 | −24.99 | |
| Country | 0.110 | 0.885 | 0.755-1.038 | 0.05 | 38.44 | |
| HWE | 0.585 | 0.706 | 0.160-3.102 | 0.11 | −25.19 | |
| Ethnicity | 0.948 | 1.021 | 0.492-2.117 | 0.11 | −30.05 | |
| Genotyping method | 0.428 | 0.721 | 0.281-1.848 | 0.09 | −3.97 | |
| Diagnostic criteria | 0.428 | 0.721 | 0.281-1.848 | 0.09 | −3.97 | |
| 1F vs. 2 | Publication year | 0.705 | 0.988 | 0.916-1.066 | 0.20 | −17.04 |
| Sample size | 0.832 | 1.000 | 0.995-1.003 | 0.21 | −22.10 | |
| Quality of study | 0.940 | 0.964 | 0.305-3.050 | 0.22 | −29.47 | |
| Country | 0.086 | 0.850 | 0.701-1.032 | 0.07 | 61.45 | |
| HWE | 0.419 | 0.456 | 0.050-4.176 | 0.17 | −2.65 | |
| Ethnicity | 0.876 | 0.921 | 0.265-3.202 | 0.21 | −24.81 | |
| Genotyping method | 0.688 | 0.763 | 0.159-3.658 | 0.20 | −19.45 | |
| Diagnostic criteria | 0.688 | 0.763 | 0.159-3.658 | 0.20 | −19.45 | |
| 1F-1F vs. 1F-1S+1S-1S+2-1S+2-1F+2-2 | Publication year | 0.193 | 0.952 | 0.875-1.036 | 0.15 | 36.06 |
| Sample size | 0.649 | 0.999 | 0.993-1.004 | 0 .26 | −7.70 | |
| Quality of study | 0.442 | 0.624 | 0.146-2.668 | 0.22 | 5.52 | |
| Country | 0.022 | 0.796 | 0.665-0.953 | 0 | 100.00 | |
| HWE | 1.000 | 1.000 | 0.020-50.838 | 0.28 | −18.90 | |
| Ethnicity | 0.722 | 1.322 | 0.197-8.890 | 0.26 | −8.51 | |
| Genotyping method | 0.391 | 0.459 | 0.054-3.874 | 0.24 | 0.57 | |
| Diagnostic criteria | 0.391 | 0.459 | 0.054-3.874 | 0.24 | 0.57 | |
| 2-2 vs. 1F-1F+1F-1S+1S-1S+2-1S+2-1F | Publication year | 0.975 | 0.998 | 0.879-1.133 | 0.83 | −34.77 |
| Sample size | 0.121 | 1.004 | 0.999-1.001 | 0.46 | 24.58 | |
| Quality of study | 0.418 | 0.536 | 0.093-3.102 | 0.67 | −9.71 | |
| Country | 0.021 | 1.468 | 1.084-1.989 | 0.13 | 78.87 | |
| HWE | 0.268 | 5.527 | 0.179-170.834 | 0.60 | 2.92 | |
| Ethnicity | 0.212 | 2.621 | 0.485-14.152 | 0.599 | 2.23 | |
| Genotyping method | 0.693 | 0.641 | 0.047-8.808 | 0.812 | −32.43 | |
| Diagnostic criteria | 0.693 | 0.641 | 0.047-8.808 | 0.812 | −32.43 |
95% CI, 95% confidence interval; HWE, Hardy-Weinberg equilibrium.