Table 7.
Level of evidence for the association of later factors and psychotic disorders
| Factor | k |
Random‐effects measure, ES (95% CI) |
Features used for classification of level of evidence | eOR | CE | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| N | p random‐effects | I2 (p) | PI (95% CI) | SSE/ESB | LS | |||||
| Childhood trauma54 | 20 | OR, 2.87 (2.07‐3.98) | 2,363 | 2.5 × 10−14 | 77% (<0.001) | 0.75‐11.01 | No/Yes | No | 2.87 | III |
| Toxoplasma gondii IgG95 | 42 | OR, 1.82 (1.51‐2.18) | 8,796 | 2.1 × 10−10 | 78% (<0.001) | 0.68‐4.88 | Yes/Yes | No | 1.82 | III |
| Toxocara spp83 | 1 | OR, 41.61 (9.71‐178.32) | 98 | 5.1 × 10−7 | NA (1.00) | NA | NA/NA | Yes | 41.61 | IV |
| Chlamydia psittaci83 | 2 | OR, 29.05 (8.91‐94.69) | 82 | 2.2 × 10−8 | 0% (0.71) | NA | NA/NA | Yes | 29.05 | IV |
| Human endogenous retrovirus type W83 | 5 | OR, 19.78 (6.50‐60.22) | 256 | 1.4 × 10−7 | 33% (0.20) | 1.05‐372.34 | No/No | Yes | 19.78 | IV |
| Parental communication deviance88 | 4 | g, 1.35 (0.97‐1.73) | 74 | 2.3 × 10−12 | 0% (0.41) | 0.51‐2.19 | No/No | No | 11.55 | IV |
| Chlamydia pneumoniae90 | 3 | OR, 6.02 (2.86‐12.66) | 116 | 2.1 × 10−6 | 0% (0.57) | 0.05‐745.30 | No/No | Yes | 6.02 | IV |
| Traffic84 | 1 | RR, 5.55 (1.63‐18.87) | 29 | 0.006 | NA (<0.001) | NA | NA/NA | Yes | 5.55 | IV |
| Adult life events85 | 6 | OR, 5.34 (3.84‐7.43) | 317 | 2.1 × 10−23 | 3% (0.39) | 3.22‐8.87 | No/No | Yes | 5.34 | IV |
| Heavy cannabis use93 | 2 | OR, 5.17 (3.64‐7.36) | 748 | 6.3 × 10−20 | 42% (0.18) | NA | NA/NA | Yes | 5.17 | IV |
| Benzene84 | 1 | RR, 3.20 (1.01‐10.12) | 29 | 0.048 | NA (1.00) | NA | NA/NA | Yes | 3.20 | IV |
| Tobacco use89 | 6 | RR, 2.19 (1.36‐3.53) | 8,488 | 0.001 | 99% (<0.001) | 0.38‐12.50 | No/No | Yes | 2.19 | IV |
| Borna disease virus83 | 21 | OR, 1.94 (1.30‐2.91) | 1,919 | 0.001 | 36% (0.05) | 0.65‐5.81 | No/No | Yes | 1.94 | IV |
| Traumatic brain injury94 | 8 | OR, 1.49 (1.09‐2.05) | 9,653 | 0.013 | 78% (<0.001) | 0.57‐3.89 | Yes/No | No | 1.49 | IV |
| Human herpes virus 283 | 5 | OR, 1.44 (1.14‐1.81) | 901 | 0.002 | 0% (0.97) | 0.99‐2.09 | No/No | Yes | 1.44 | IV |
| Chlamydia trachomatis83 | 2 | OR, 4.39 (0.03‐587.92) | 82 | 0.554 | 85% (0.01) | NA | NA/NA | No | 4.39 | ns |
| Human endogenous retrovirus83 | 4 | OR, 3.64 (0.72‐18.37) | 128 | 0.117 | 36% (0.19) | 0.01‐1019 | No/No | Yes | 3.64 | ns |
| Tetrachloroethylene84 | 1 | RR, 3.41 (0.48‐24.24) | 4 | 0.219 | NA (1.00) | NA | NA/NA | No | 3.41 | ns |
| Carbon monoxide84 | 1 | RR, 3.07 (0.96‐9.82) | 29 | 0.059 | NA (1.00) | NA | NA/NA | No | 3.07 | ns |
| Epilepsy86 | 1 | OR, 3.06 (0.31‐29.95) | 4 | 0.337 | NA (1.00) | NA | NA/NA | No | 3.06 | ns |
| Nitrogen oxides84 | 1 | RR, 2.02 (0.74‐5.53) | 29 | 0.171 | NA (1.00) | NA | NA/NA | No | 2.02 | ns |
| Central nervous system infection during childhood91 | 2 | RR, 1.99 (0.31‐12.78) | 2,369 | 0.466 | 80% (0.02) | NA | NA/NA | No | 1.99 | ns |
| Epstein‐Barr virus83 | 3 | OR, 1.98 (0.23‐16.85) | 55 | 0.532 | 0% (0.81) | 0‐2121495 | No/No | No | 1.98 | ns |
| Nitrogen dioxide84 | 1 | RR, 1.91 (0.70‐5.19) | 29 | 0.205 | NA (1.00) | NA | NA/NA | No | 1.91 | ns |
| Hearing impairment92 | 5 | OR, 1.64 (0.85‐3.15) | 597 | 0.141 | 76% (0.002) | 0.18‐15.17 | No/No | Yes | 1.64 | ns |
| Toxoplasma gondii IgM95 | 15 | OR, 1.24 (0.97‐1.59) | 2,867 | 0.083 | 2% (0.43) | 0.91‐1.70 | No/No | No | 1.24 | ns |
| Human herpes virus 190 | 11 | OR, 1.24 (0.98‐1.58) | 1,117 | 0.074 | 5% (0.39) | 0.87‐1.78 | No/No | No | 1.24 | ns |
| Cytomegalovirus83 | 8 | OR, 1.20 (0.65‐2.20) | 171 | 0.558 | 0% (1.00) | 0.56‐2.56 | No/No | No | 1.20 | ns |
| Varicella zoster virus83 | 4 | OR, 1.17 (0.16‐8.58) | 69 | 0.878 | 0% (0.99) | 0.01‐92.93 | No/No | No | 1.17 | ns |
| BK virus83 | 1 | OR, 1.05 (0.02‐55.41) | 20 | 0.979 | NA (1.00) | NA | NA/NA | No | 1.05 | ns |
| JC virus83 | 1 | OR, 1.05 (0.02‐55.41) | 20 | 0.979 | NA (1.00) | NA | NA/NA | No | 1.05 | ns |
| Human endogenous retrovirus type k11583 | 1 | OR, 0.89 (0.43‐1.84) | 178 | 0.753 | NA (1.00) | NA | NA/NA | No | 0.89 | ns |
| Influenza83 | 2 | OR, 0.87 (0.05‐15.48) | 33 | 0.925 | 0% (0.92) | NA | NA/NA | No | 0.87 | ns |
| Human T‐lymphotropic virus 183 | 2 | OR, 0.57 (0.20‐1.62) | 209 | 0.294 | 0% (0.87) | NA | NA/NA | No | 0.57 | ns |
| Bullying87 | 1 | OR, 0.38 (0.13‐1.10) | 30 | 0.075 | NA (1.00) | NA | NA/NA | No | 0.38 | ns |
| Human herpes virus 690 | 3 | OR, 0.34 (0.05‐2.42) | 55 | 0.284 | 0% (0.71) | 0‐106440 | No/No | No | 0.34 | ns |
k – number of samples for each factor, ES – effect size, N – number of cases, PI – prediction interval, CI – confidence interval, SSE – small‐study effect, ESB – excess significance bias, LS – largest study with significant effect, eOR – equivalent odds ratio, CE – class of evidence, IRR – incidence rate ratio, OR – odds ratio, RR – relative risk, Ig – immunoglobulin, NA – not assessable, ns – not significant