Predictors | Studies/strata | Samples | Univariable analyses | Variance explained | |||
Total N | Total N | OR (95% CI) | P value* | R2 (%) | |||
Population characteristics | WHO region | AMRO | 33 | 7960 | 1.00 | 5.1 | |
AFRO | 24 | 2281 | 3.95 (1.54 to 10.09) | 0.004 | |||
EMRO | 14 | 1550 | 1.37 (0.45 to 4.19) | 0.576 | |||
EURO | 73 | 8987 | 1.32 (0.64 to 2.76) | 0.452 | |||
SEARO | 15 | 1207 | 1.24 (0.42 to 3.70) | 0.692 | |||
WPRO | 19 | 4905 | 1.23 (0.45 to 3.37) | 0.686 | |||
Multicenter | 6 | 374 | 8.96 (1.90 to 42.29) | 0.006 | |||
Sex | Men | 43 | 16 560 | 1.00 | 2.0 | ||
Women | 141 | 10 704 | 1.98 (1.06 to 3.67) | 0.031 | |||
Infertility type | Primary/majority primary | 52 | 9330 | 1.00 | 0.7 | ||
Secondary/majority secondary | 24 | 1756 | 2.14 (0.88 to 5.17) | 0.091 | |||
Not specified/not applicable | 108 | 16 178 | 1.06 (0.58 to 1.95) | 0.840 | |||
Infertility diagnosis | General infertility/not specified | 64 | 12 441 | 1.00 | 4.7 | ||
Tubal factor infertility | 50 | 3238 | 2.39 (1.23 to 4.63) | 0.010 | |||
Male factor infertility | 24 | 8263 | 0.72 (0.31 to 1.67) | 0.442 | |||
Ovarian and non-tubal infertility | 26 | 2255 | 0.80 (0.36 to 1.81) | 0.595 | |||
Mixed and unexplained infertility | 20 | 1067 | 2.03 (0.83 to 4.98) | 0.122 | |||
Presence of urogenital signs and symptoms | Asymptomatic | 64 | 16 484 | 1.00 | 8.2 | ||
Symptomatic | 24 | 1408 | 5.94 (2.61 to 13.54) | <0.001 | |||
Not specified | 96 | 9372 | 1.67 (0.96 to 2.91) | 0.070 | |||
Study methodology characteristics | Assay type | NAAT (current infection) | 33 | 12 594 | 1.00 | 22.0 | |
Culture (current infection) | 94 | 9682 | 2.54 (1.34 to 4.83) | 0.005 | |||
Other† (current infection) | 7 | 458 | 4.08 (1.09 to 15.27) | 0.037 | |||
IgG (ever infection) | 25 | 1470 | 22.10 (9.53 to 51.20) | <0.001 | |||
IgA/unclear | 25 | 3060 | 3.74 (1.61 to 8.67) | 0.002 | |||
Year of data collection‡ | 184 | 27 264 | 0.97 (0.95 to 0.99) | 0.001 | 5.5 | ||
Sample size | <100 participants | 81 | 3803 | 1.00 | 3.0 | ||
≥100 participants | 103 | 23 461 | 0.51 (0.30 to 0.86) | 0.011 | |||
Risk of bias domains | Infertility definition | Follows WHO definition | 70 | 11 293 | 1.00 | 0 | |
Otherwise/unclear | 114 | 15 971 | 0.85 (0.49 to 1.46) | 0.549 | |||
Exposure to antimicrobials | Lack of exposure last week | 25 | 2037 | 1.00 | 2.2 | ||
Exposure in last week | 9 | 1503 | 0.91 (0.23 to 3.61) | 0.890 | |||
Unclear | 150 | 23 724 | 2.27 (1.06 to 4.90) | 0.036 | |||
Infection ascertainment | Consistency in assay used | 179 | 26 612 | 1.00 | 0 | ||
Otherwise/Unclear | 5 | 652 | 1.30 (0.25 to 6.66) | 0.750 | |||
Response rate | ≥80% | 2 | 70 | 1.00 | 0 | ||
<80%/unclear | 182 | 27 194 | 0.78 (0.06 to 10.10) | 0.849 |
*Strength of evidence for an association with prevalence was deemed ‘good’ at 0.05<p value≤0.10, and ‘strong’ at p value≤0.05.
†Includes Gram stain, gonozyme and fluorescent antibody assays.
‡Missing values for year of data collection were imputed using data for year of publication adjusted by the median difference between year of publication and year of data collection (for studies with complete information).
AFRO, African Region; AMRO, Region of the Americas; EMRO, Eastern Mediterranean Region; EURO, European Region; NAAT, nucleic acid amplification test; NG, Neisseria gonorrhoeae; SEARO, South-East Asia Region; WPRO, Western Pacific Region.