Table 3.
Subgroup analyses.
| BC recurrence | BC mortality | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Study characteristics | Datasets number | HR (95% CI) | I2 (%) | P for subgroup effect | P for subgroup difference | Datasets number | HR (95% CI) | I2 (%) | P for subgroup effect | P for subgroup difference |
| Study design | ||||||||||
| PC | 3 | 0.81 [0.69, 0.95] | 0 | 0.009 | 5 | 0.76 [0.63, 0.91] | 76 | 0.004 | ||
| RC | 7 | 0.67 [0.50, 0.90] | 39 | 0.008 | 0.26 | 4 | 0.87 [0.78, 0.97] | 0 | 0.009 | 0.23 |
| Sample size | ||||||||||
| <1,000 | 6 | 0.64 [0.44, 0.94] | 42 | 0.02 | 3 | 0.91 [0.63, 1.31] | 0 | 0.60 | ||
| ≥1,000 | 4 | 0.80 [0.69, 0.93] | 0 | 0.003 | 0.29 | 6 | 0.79 [0.70, 0.90] | 71 | <0.001 | 0.51 |
| Follow-up duration (years) | ||||||||||
| ≤ 5 | 4 | 0.55 [0.42, 0.72] | 0 | <0.001 | 5 | 0.79 [0.66, 0.95] | 77 | 0.01 | ||
| >5 | 6 | 0.83 [0.72, 0.96] | 0 | 0.01 | 0.009 | 4 | 0.81 [0.73, 0.91] | 0 | <0.001 | 0.80 |
| Adjustment of menopausal status | ||||||||||
| Yes | 4 | 0.75 [0.56, 1.01] | 66 | 0.06 | 3 | 0.71 [0.44, 1.14] | 68 | 0.15 | ||
| No | 6 | 0.63 [0.47, 0.84] | 0 | 0.002 | 0.40 | 6 | 0.85 [0.80, 0.91] | 0 | <0.001 | 0.44 |
| Adjustment of hormonal receptor status | ||||||||||
| Yes | 9 | 0.72 [0.58, 0.88] | 33 | 0.002 | 4 | 0.86 [0.71, 1.04] | 0 | 0.12 | ||
| No | 1 | 0.67 [0.39, 1.14] | — | 0.14 | 0.81 | 5 | 0.78 [0.68, 0.91] | 77 | 0.001 | 0.47 |
| Adjustment of comorbidities | ||||||||||
| Yes | 3 | 0.76 [0.47, 1.22] | 42 | 0.25 | 5 | 0.87 [0.81, 0.94] | 0 | <0.001 | ||
| No | 7 | 0.70 [0.56, 0.87] | 31 | 0.002 | 0.76 | 4 | 0.71 [0.55, 0.92] | 74 | 0.009 | 0.13 |
| NOS Score | ||||||||||
| 6–7 | 8 | 0.68 [0.51, 0.89] | 28 | 0.006 | 2 | 0.88 [0.77, 1.01] | 0 | 0.07 | ||
| 8–9 | 2 | 0.77 [0.61, 0.98] | 32 | 0.03 | 0.48 | 7 | 0.78 [0.68, 0.90] | 64 | <0.001 | 0.25 |
BC, breast cancer; HRa, hazard ratio; CI, confidence interval; PC, prospective cohort; RC, retrospective cohort; NOS, the Newcastle-Ottawa Scale.