Table 4.
The Moderating Effect of Environmental Factors on the Risk of Delusions Given Hallucinations
| Exposure type | n a | Proportion exposed, % (n) |
Proportion with delusions given absence of hallucinations, % (n) | Proportion with delusions given presence of hallucinations, % (n) | Difference (%) | Effect size environmental factor (%) | Interaction χ2, p |
|---|---|---|---|---|---|---|---|
| Cannabis urinalysis + | 1827 | 6.2 (114) |
10 (10) | 73.3 (11) | 63.3 | 31.6 | χ2 = 4.3, p = .037 |
| Cannabis urinalysis − | 93.8 (1713) |
6.2 (100) | 37.9 (33) | 31.7 | |||
| Childhood trauma + | 2628 | 51.5 (1352) | 8.1 (62) | 44.6 (25) | 36.5 | 15.2 | χ2 = 3.7, p = .054 |
| Childhood trauma − | 48.6 (1276) |
6.8 (33) | 28.1 (9) | 21.3 | |||
| Urbanicity <age 15 + | 3072 | 47.5 (1612) | 5.6 (47) | 52.1 (25) | 46.5 | 14.4 | χ2 = 0.9, p = .357 |
| Urbanicity <age 15 − | 52.5 (1460) |
7.0 (60) | 39.1 (18) | 32.1 |
Note: aAll analyses carried out in combined data of the control and sibling group and refer to multilevel logistic regression analyses controlled for age, sex, group, and clustering of observations within subjects, with delusions as dependent variable and the “any T0 or T1 hallucination × environmental factor” interaction as independent variable.