Table 2.
Subgroup and meta-regression analyses of lifetime and point prevalence of suicidal ideation in patients with schizophrenia.
| Subgroup analyses | ||||||||
|---|---|---|---|---|---|---|---|---|
| Subgroupsa | Categories (number of studies) | Events | Sample size | Prevalence (%) | 95% CI (%) | I2 (%) | P values within subgroups | Q (P values across subgroups) |
| Lifetime | ||||||||
| Gender | Male (6) | 188 | 509 | 36.9 | 31.0–43.2 | 0 | 0.518 | 0.092 (0.762) |
| Female (5) | 137 | 403 | 35.4 | 28.3–43.1 | 62.3 | 0.031 | ||
| Source of patients | Outpatients (4) | 427 | 1233 | 42.2 | 27.3–58.8 | 96.4 | <0.001 | 3.095 (0.079) |
| Inpatients (4) | 188 | 768 | 23.8 | 13.8–37.9 | 83.6 | <0.001 | ||
| Survey country | High-income (6) | 245 | 749 | 38.9 | 28.8–50.0 | 81.1 | <0.001 | 1.384 (0.239) |
| Low- or middle-income (8) | 786 | 2375 | 30.9 | 23.6–39.3 | 94.0 | <0.001 | ||
| Sample size | ≤110 (7) | 183 | 495 | 38.0 | 29.0–48.0 | 60.5 | 0.019 | 1.289 (0.256) |
| >110 (7) | 848 | 2629 | 30.8 | 23.4–39.3 | 95.2 | <0.001 | ||
| Measure of instrument | Scale (10) | 584 | 1599 | 34.2 | 27.3–41.9 | 88.1 | <0.001 | 0.010 (0.921) |
| Non-scale (4) | 447 | 1525 | 33.5 | 23.7–45.1 | 93.5 | <0.001 | ||
| Point | ||||||||
| Gender | Male (7) | 200 | 679 | 33.4 | 24.2–44.1 | 85.2 | <0.001 | 0.580 (0.446) |
| Female (6) | 135 | 547 | 27.8 | 18.9–38.9 | 79.7 | <0.001 | ||
| Source of patients | Outpatient (3) | 190 | 775 | 27.7 | 19.9–37.2 | 81.8 | 0.004 | 9.553 (0.008) |
| Inpatient (5) | 342 | 967 | 38.5 | 30.8–46.8 | 76.5 | 0.002 | ||
| Mixed (3) | 57 | 312 | 20.0 | 13.3−29.0 | 79.7 | 0.007 | ||
| Survey country | High-income (7) | 403 | 1171 | 36.4 | 30.1–43.3 | 67.5 | 0.005 | 10.725 (0.001) |
| Low- or middle-income (6) | 244 | 1157 | 22.0 | 17.0–27.8 | 83.2 | <0.001 | ||
| Sampling method | Probability sampling (3) | 148 | 671 | 23.7 | 15.4–34.8 | 22.7 | 0.331 | 2.018 (0.155) |
| Non-probability sampling (8) | 379 | 1216 | 32.9 | 26.2–40.3 | 85.5 | <0.001 | ||
| Average education year | ≤11.6 (4) | 185 | 881 | 21.7 | 13.2–33.5 | 83.8 | <0.001 | 1.283 (0.257) |
| >11.6 (4) | 132 | 453 | 31.1 | 19.9–45.2 | 91.4 | <0.001 | ||
| Sample size | ≤118 (7) | 207 | 579 | 35.4 | 27.6–43.9 | 68.3 | 0.004 | 4.499 (0.034) |
| >118 (6) | 443 | 1749 | 24.0 | 18.0–31.1 | 91.0 | <0.001 | ||
| Measure of instrument | Scale (9) | 347 | 1342 | 28.6 | 23.0–34.9 | 81.4 | <0.001 | 2.471 (0.116) |
| Non-scale (3) | 280 | 805 | 38.4 | 28.0–50.0 | 84.6 | 0.002 | ||
| Meta-regression analyses | ||||||
|---|---|---|---|---|---|---|
| Covariates | Coefficient | Standard error | 95% lower | 95% upper | z value | P value |
| Lifetime | ||||||
| Survey time | 0.0428 | 0.0051 | 0.0327 | 0.0529 | 8.34 | <0.001 |
| Male proportion | 0.0165 | 0.0034 | 0.0098 | 0.0232 | 4.81 | <0.001 |
| Mean age (years) | −0.0464 | 0.0077 | −0.0616 | −0.0313 | −6.01 | <0.001 |
| Study quality assessment | 0.2387 | 0.0357 | 0.1688 | 0.3086 | 6.69 | <0.001 |
| Point | ||||||
| Male proportion (%) | 0.0196 | 0.0043 | 0.0112 | 0.0279 | 4.60 | <0.001 |
| Mean age (years) | 0.0022 | 0.0125 | −0.0223 | 0.0267 | 0.18 | 0.860 |
| Duration of illness (years) | 0.0138 | 0.0152 | −0.0160 | 0.0437 | 0.91 | 0.363 |
| Study quality assessment | −0.1963 | 0.0525 | −0.2992 | −0.0934 | −3.74 | <0.001 |
CI confidence interval.
aContinuous variables in subgroup analyses were divided according to median splitting method.