Table 2. Results of subgroup and sensitivity analyses.
| Outcome | Results (n) | Heterogeneity |
|---|---|---|
| Subgroup analysis | ||
| • Sleepiness | ≥ Mild (n = 4): SMD (95% CI) = -0.35 (-1.21; 0.50) | I2 = 77% |
| Mild (n = 2): SMD (95% CI) = -2.08 (-2.84; -1.33) | I2 = 28% | |
| Subgroup difference: χ2–9.13, df = 1, p < 0.01 | ||
| • Sleep disturbance | ≥ Mild (n = 3): SMD (95% CI) = -0.64 (-1.13; -0.15) | I2 = 0% |
| Mild (n = 2): SMD (95% CI) = -0.60 (-2.27; 1.07) | I2 = 89% | |
| Subgroup difference: χ2–0.00, df = 1, p = 0.97 | ||
| • Depressive symptoms | ≥ Mild (n = 2): SMD (95% CI) = -1.25 (-1.89; -0.62) | I2 = 0% |
| Mild (n = 2): SMD (95% CI) = -0.79 (-2.00; 0.41) | I2 = 80% | |
| Subgroup difference: χ2–0.44, df = 1, p = 0.51 | ||
| • Fatigue | ≥ Mild (n = 4): SMD (95% CI) = -1.44 (-2.95; 0.08) | I2 = 91% |
| (No trials in mild TBI) | ||
| • Dropout rates | ≥ Mild (n = 4): RR (95% CI) = 0.56 (0.24; 1.30) | I2 = 0% |
| Mild (n = 2): RR (95% CI) = 1.07 (0.18; 6.39) | I2 = 0% | |
| Subgroup difference: χ2 = 0.41, df = 1, p = 0.52 | ||
| Sensitivity analysis | ||
| • Sleepiness | n = 3: SMD (95% CI) = -1.39 (-2.76; -0.03), p for z-score = 0.05 | I2 = 93% |
| • Sleep disturbance | n = 2: SMD (95% CI) = -0.60 (-2.27; 1.07), p for z-score = 0.48 | I2 = 89% |
| • Depressive symptoms | n = 2: SMD (95% CI) = -0.79 (-2.00; 0.41), p for z-score = 0.20 | I2 = 80% |
| • Fatigue | n = 1: SMD (95% CI) = -0.13 (-0.40; 0.22), p for z-score = N/A | I2 = N/A |
| • Dropout rates | n = 3: RR (95% CI) = 0.76 (0.35; 1.65), p for z-score = 0.49 | I2 = 1% |
SMD: standardized mean difference; RR: risk ratio; TBI: traumatic brain injury.