Table 1.
Overview of studies included in systematic review
| Comparison by population | No of studies (No of patients) | No of studies providing data for primary outcome | Years of publication (median) | Countries of study | Risk of bias |
|---|---|---|---|---|---|
| Steroid v placebo: | |||||
| Inpatients | 9 (772) | 8 | 1996-2007 (2000) | UK (2), Israel, Belgium, Mexico, Canada, Thailand, Brazil, USA | 1 low, 4 unclear, 4 high |
| Outpatients | 8 (1778) | 8 | 1998-2009 (2002/2004) | USA (2), Canada (2), Turkey (2), Israel, Paraguay | 1 low, 4 unclear, 3 high |
| Adrenaline v placebo: | |||||
| Inpatients | 3 (330) | 2 | 2002-3 (2002) | England, Canada, Australia | 1 low, 1 unclear, 1 high |
| Outpatients | 5 (526) | 4 | 1995-2009 (2005) | Turkey (2), Iran, Canada, USA | 2 low, 2 unclear, 1 high |
| Salbutamol* or terbutaline v placebo: | |||||
| Inpatients: | 9 (488) | 6 | 1991-2009 (1997) | Turkey (2), France, Saudi Arabia, Singapore, Canada, USA, Tunisia, Australia | 1 low, 5 unclear, 3 high |
| Outpatients | 11 (926) | 6 | 1990-2008 (1998) | Canada (3), Turkey (3), USA (2), Egypt, India, Iran | 2 low, 6 unclear, 3 high |
| Ipratropium v placebo: | |||||
| Inpatients | 3 (194) | 2 | 1995-2008 (1997) | Saudi Arabia, Singapore, Turkey | 3 unclear |
| Outpatients | 1 (72) | 1 | 1992 | Canada | 1 unclear |
| Adrenaline and dexamethasone v other: | |||||
| Inpatients | 0 | NA | NA | NA | NA |
| Outpatients | 2 (436) | 2 | 2004, 2009 | Turkey, Canada | 1 low, 1 high |
| Ipratropium and salbutamol* v placebo: | |||||
| Inpatients | 0 | NA | NA | NA | NA |
| Outpatients | 1 (72) | 1 | 1992 | Canada | 1 unclear |
| Steroid v adrenaline: | |||||
| Inpatients | 0 | NA | NA | NA | NA |
| Outpatients | 2 (444) | 2 | 1995, 2009 | Turkey, Canada | 1 low, 1 high |
| Adrenaline v salbutamol*: | |||||
| Inpatients | 6 (433) | 4 | 1993-2007 (2001/2002) | Canada (2), Jordan, Chile, Iran, India | 1 low, 3 unclear, 2 high |
| Outpatients | 8 (378) | 6 | 1995-2007 (2004) | Turkey (3), USA (2), Israel, Iran, Canada, | 4 low, 3 unclear, 1 high |
| Steroid v salbutamol*: | |||||
| Inpatients | 0 | NA | NA | NA | NA |
| Outpatients | 1 (45) | 1 | 1995 | Turkey | 1 high |
| Salbutamol v ipratropium: | |||||
| Inpatients | 4 (192) | 3 | 1995-2008 (2000) | Saudi Arabia, Singapore, Turkey (2) | 3 unclear, 1 high |
| Outpatients | 0 | NA | NA | NA | NA |
| Steroid and salbutamol* v other: | |||||
| Inpatients | 0 | NA | NA | NA | NA |
| Outpatients | 2 (103) | 2 | 1998, 2004 | Turkey (2) | 2 high |
NA=Not applicable.
*Salbutamol has been used throughout to also refer to albuterol.