Analysis | Outcome or moderator variables | Number of included studies | Odds ratio (95% confidence interval) | I2, % | p for mixed-effects meta-regression analysis |
---|---|---|---|---|---|
Main analysis | Short-term survival | 0.71 (0.59–0.85) | 86 | NA | |
Subgroup analysis | |||||
Study period | Before 2010 | 1 [19] | 0.58 (0.48–0.70) | 0 | 0.39 |
After 2010 | 0.73 (0.60–0.89) | 87 | |||
Study region | North America | 0.74 (0.59–0.94) | 88 | 0.36 | |
Europe | 0.62 (0.23–1.69) | 40 | |||
Selection of vascular access | First attempted vascular access | 0.70 (0.50–0.98) | 90 | 0.90 | |
Actual vascular access | 0.72 (0.49–1.04) | 82 | |||
EMS response time | Longer than 10 mins | 0.59 (0.09–4.02) | 67 | 0.24 | |
Shorter than 10 mins | 0.75 (0.61–0.92) | 87 | |||
Time to intervention | Timing adjusted in analysis | 0.77 (0.64–0.92) | 76 | 0.25 | |
Timing not adjusted in analysis | 0.64 (0.39–1.05) | 85 | |||
Type of effect estimates pooled in analysis | Adjusted effect estimates | 0.73 (0.61–0.88) | 82 | 0.55 | |
Unadjusted effect estimates | 0.66 (0.25–1.70) | 88 | |||
Initial arrest rhythm | Shockable rhythms | 0.72 (0.48–1.09) | 80 | NA | |
Main analysis | Survival at hospital discharge | 0.66 (0.42–1.04) | 89 | NA | |
Subgroup analysis | |||||
Study period | Before 2010 | 1 [19] | 0.40 (0.26–0.61) | 0 | 0.31 |
After 2010 | 0.72 (0.44–1.19) | 88 | |||
Study region | North America | 0.75 (0.47–1.20) | 86 | 0.30 | |
Europe | 0.45 (0.0003–521.08) | 87 | |||
Selection of vascular access | First attempted vascular access | 0.64 (0.24–1.69) | 90 | 0.84 | |
Actual vascular access | 0.68 (0.25–1.85) | 87 | |||
EMS response time | Longer than 10 mins | 1 [22] | 0.76 (0.47–1.23) | 0 | 0.79 |
Shorter than 10 mins | 0.64 (0.37–1.13) | 92 | |||
Time to intervention | Timing adjusted in analysis | 0.83 (0.64–1.08) | 66 | 0.01 | |
Timing not adjusted in analysis | 0.34 (0.02–5.91) | 31 | |||
Type of effect estimates pooled in analysis | Adjusted effect estimates | 0.75 (0.53–1.07) | 81 | 0.06 | |
Unadjusted effect estimates | 1 [24] | 0.25 (0.13–0.47) | 0 | ||
Initial arrest rhythm | Shockable rhythms | 0.78 (0.44–1.41) | 80 | NA |