Subsequently, the investigators used Pubmed to search the Medline database for other randomised controlled trials comparing the effects of salmeterol (or other long-acting beta2 agonist) with montelukast (or other leukotriene antagonist) within the context of Arg/Gly variation, in children with asthma. No studies could be identified. In particular, there are no trials in either adults or children that have studied quality-of-life, which is a key outcome of interest in the context of asthma-related disability, and which is often unrelated to outcomes such as lung function. This led to the development of the Personalised Medicine for Asthma Control (PACT)-study, a randomised controlled trial to determine if personalised medicine improves quality of life and asthma control in 12-18 years olds. Results of this trial when published, will provide more conclusive evidence as to the effectiveness of personalised medicine in this age group. However, there is an absence of trials in a younger age group of children with asthma (5-11 years) and no evidence to determine if a personalised medicine clinic is feasible within a hospital setting, which underscores the need for this study.