Asthma exacerbations are a serious and concerning problem in children with asthma. This study will enable us to assess whether mathematical modelling of fluctuation patterns can enable us to predict n asthma attack and therefore intervene before it becomes severe or even life threatening. This study will also enable us to investigate the relationship between symptoms, peak flow patterns, exacerbations and adherence to inhaled corticosteroids (ICS) as measured by electronic recording devices (Smart-inhalers).