Table 2

Relative effects of longer door-to-balloon delay (vs shorter) on myocardial infarction with ST-segment elevation mortality by subgroup factors

SubgroupCohorts (n)Effect estimates (95% CI)I2 (%)Interaction P value*
Risk profile
 Higher risk323 30 42 1.81 (1.46 to 2.24)0.00.58
 Lower risk323 30 42 1.69 (1.50 to 1.89)25.0
Data source
 Registry/EMR1716 18 20 21 23 24 26 30 32 33 36–39 41 49 50 1.43 (1.26 to 1.63)46.60.50
 Clinical trial343 47 48 1.22 (0.77 to 1.93)64.1
Prehospital delay†
 Longer2 24 46 1.06 (0.79 to 1.41)0.00.049
 Shorter319 24 46 1.48 (1.25 to 1.76)0.0
Setting
 HIC1616 18 20 21 23 24 26 30 32 33 36–39 49 50 1.43 (1.26 to 1.62)49.60.66
 LMIC141 2.22 (0.32 to 15.5)
Region
 Asia737–39 41 49 50 1.07 (0.74 to 1.55)20.00.17
 North America616 18 20 21 23 24 1.49 (1.32 to 1.69)54.6
 UK and Europe326 30 33 1.81 (1.10 to 2.95)61.9
  • Forest plots of all subgroup analyses are provided in online supplementary appendix eFigures 8.1–8.5.

  • *Test for subgroup differences (random-effects model, inverse variance method).

  • †Pooled HR analysis.

  • EMR, medical chart data; HIC, high-income country; HR , hazard ratio of mortality incidence rate; LMIC, lower middle-income country;  OR, odds ratio of short-term mortality incidence proportion.