The patients group (N = 225) will be evaluated to produce a clinical prediction rule for loss of control. The investigators will consider the following variables in the risk factor analysis: documented history of previous bronchial obstruction (FEV1/FVC < 70%), coefficient of variation (CV) of morning peak expiratory flow (PEF), history of exacerbations, fraction of exhaled nitric oxide (FENO), Asthma control test (ACT), ACT item 3 and adherence.