Table 4.
Urbanicity and psychosis risk.
| Study | Dia-gnosis | k | n1 | n2 | Statistical value and variance | Summary statistical value+ or common size effect++ and variance | I 2 | Q |
|---|---|---|---|---|---|---|---|---|
| Urbanicity | ||||||||
| Kirkbride et al. | NAP | 9 | IRR = 1.02 (1.02–1.03)*** | d = 0.01 (0.01–0.02) | ||||
| Kirkbride et al. | SCZ | 15 | IRR = 1.03 (1.01–1.03)*** | d = 0.02 (0.01–0.02) | ||||
| Castillejos et el. | NAP | 5 | IRR = 2.25 (2.00–2.52)**** | d = 0.45 (0.38–0.51) | ||||
| Castillejos et el. | SCZ | 3 | IRR = 1.64 (1.38–1.95)*** | d = 0.27 (0.18−0.37) | ||||
| Total | d = 0.57 (0.39−0.74) | 98.5 | 206.71*** | |||||
Summary effects and qualitative review of included meta-analyses. NAP, non-affective psychosis; SCZ, schizophrenia; k, number of effect sizes; n1, number of cases; n2, number of controls; IRR, incidence rate ratio; d, Cohen's d; +pooled result of several meta-analyses written in bold letters; ++one meta-analysis available, result converted in common effect size and presented qualitatively; Q, Cochran's Q heterogeneity statistics; I2, I2 index for heterogeneity. *p < 0.3; **p < 0.05; ***p < 0.01; ****p < 0.001; ns, not significant.