Table 2. Subgroup meta-analysis of clinicopathological characteristics and survival outcomes between the younger group and older group.
| Subgroup | Included studies | Included patients | I2 (%) | Effect model | OR/WMD | 95% CI | P |
|---|---|---|---|---|---|---|---|
| Female | 25 | 81,188 | 76 | Random | 2.09 | 1.81–2.41 | <0.001 |
| Diffuse type | 10 | 56,335 | 82 | Random | 4.29 | 3.15–5.85 | <0.001 |
| pTNM stage IV | 16 | 26,202 | 0 | Fixed | 1.21 | 1.08–1.35 | <0.001 |
| Poorly differentiation | 19 | 75,349 | 82 | Random | 3.59 | 2.89–4.47 | <0.001 |
| SRCC | 5 | 52,262 | 0 | Fixed | 4.81 | 4.33– 5.33 | <0.001 |
| Therapeutic regimen | |||||||
| Subtotal gastrectomy | 9 | 14,427 | 39 | Fixed | 0.88 | 0.79–0.99 | 0.03 |
| Curative gastrectomy | 14 | 18,159 | 10 | Fixed | 0.93 | 0.82–1.06 | 0.30 |
| D1 lymphadenectomy | 4 | 7,387 | 25 | Fixed | 0.59 | 0.48–0.73 | <0.001 |
| ≥ D2 lymphadenectomy | 4 | 7,387 | 27 | Fixed | 1.77 | 1.44–2.18 | <0.001 |
| Chemotherapy | 6 | 8,750 | 43 | Fixed | 1.79 | 1.49–2.16 | <0.001 |
| Postoperative complications | 5 | 6,309 | 73 | Random | 0.44 | 0.24–0.79 | 0.006 |
| Recurrence/metastasis | |||||||
| Peritoneal recurrence | 4 | 1,965 | 11 | Fixed | 1.93 | 1.31–2.84 | 0.001 |
| Lymph node metastasis | 8 | 3,901 | 0 | Fixed | 0.83 | 0.69–0.98 | 0.03 |
| Hepatic metastasis | 9 | 11,126 | 0 | Fixed | 0.68 | 0.47–0.98 | 0.04 |
| Peritoneal metastasis | 9 | 11,695 | 63 | Random | 1.63 | 1.16–2.27 | 0.004 |
| 5-year OS | 9 | 59,647 | 60 | Random | 1.01 | 0.79–1.30 | 0.92 |
| 5-year OS underwent surgery | 18 | 26,770 | 56 | Random | 1.35 | 1.16–1.57 | <0.001 |
| Stage I-OS | 8 | 6,536 | 11 | Fixed | 2.38 | 1.56–3.61 | <0.001 |
| Stage II-OS | 8 | 3,347 | 46 | Fixed | 1.28 | 0.98–1.66 | 0.07 |
| Stage III-OS | 7 | 5,702 | 27 | Fixed | 1.36 | 1.14–1.63 | <0.001 |
| Stage IV-OS | 7 | 1,483 | 0 | Fixed | 1.93 | 1.30–2.85 | 0.001 |
| 5-year OS underwent curative surgery | 12 | 19,012 | 60 | Random | 1.39 | 1.12–1.72 | 0.002 |
| Stage I-OS | 4 | 5,261 | 51 | Random | 1.73 | 0.86–3.49 | 0.13 |
| Stage II-OS | 4 | 2,771 | 51 | Random | 0.95 | 0.60–1.51 | 0.83 |
| Stage III-OS | 4 | 4,639 | 0 | Fixed | 1.29 | 1.05–1.58 | 0.01 |
| Stage IV-OS | 3 | 1,016 | 0 | Fixed | 1.86 | 1.20–2.89 | 0.006 |
pTNM, pathological (p), primary tumor (T), lymph nodes (N) and distant metastases (M); SRCC, signet ring cell carcinoma; OS, overall survival.