1. FDA study design.
| Study | Run‐in period ≥ 16 weeks | Tx period ≥ 48 weeks | Follow‐up period (to access catch‐up period) | Follow‐up period ≥ 8 weeks | Recommended age (male: 3‐10.5 years; female: 3‐9.5 years, prepuberty (Tanner 1)) | Mild asthma severity | No use of spacers | Placebo or active control group with no growth‐suppressing effect |
| Allen 1998 | No (2 weeks) | Yes (52 weeks) | No | No | Yes | Yes | Yes | Yes |
| Brand 2011 | No (2‐4 weeks) | No (24 weeks) | No | No | Partially (2‐6 years) | Yes | No | Yes (placebo or montelukast if control was insufficient) |
| Pedersen 2010 | No (2‐4 weeks) | No (12 weeks) | No | No | Yes (6‐11 years) | No | No* | Yes |
| Shapiro 1998 | No (2 weeks) |
No (12 weeks) | No | No | No (6‐18 years) | No | Yes | Yes |
| Skoner 2008 | Yes (6 months) | Yes (52 weeks) | Yes | Yes (8 weeks) | Yes (5‐8 years) | Yes | Yes | Yes |
| Skoner 2011 | No (1‐2 weeks) | Yes (52 weeks) | Yes | Yes (12 weeks) | Yes | Yes | No | Yes |
| Sorkness 2007 | No (2‐4 weeks) | Yes (48 weeks) | No | No | No (6‐14 years) | No (mild to moderate) | No | Yes (montelukast) |
| Vaessen‐Verberne 2010 | No (6 weeks) | No (26 weeks) | No | No | No (6‐16 years) | No (moderate) | Yes | No |
| Verbern 1998 | No (6 weeks) | Yes (54 weeks) | Yes+ | No | No (6‐16 years) | No | Yes | Yes (salmeterol) |
| Wasserman 2006 | No (2‐4 weeks) | No (12 weeks) | No | No | Partially (24‐47 months) | NR | No | Yes |
FDA = US Food and Drug Administration; NR = not reported.
All studies were randomised, placebo‐controlled, double‐blind, parallel‐group trials.