Seretide Versus Flixotide In Asthmatic Children Not Controlled By Inhaled Corticosteroids

Inclusion criteria: * A documented clinical history of asthma for a period of at least 6 months. * A documented history (within 12 months of Visit 1) of airway reversibility of = 15% based either on Forced expiratory volume (FEV1) or PEF measured pre and post inhalation of 200 mcg salbutamol. (If no documented history of reversibility exists, patients must demonstrate a =15% reversibility at Visit 1). * Receiving an inhaled corticosteroid at a medium dose (beclomethasone dipropionate HydroFluoroAlkane (HFA) non fine particle = 400-500 mcg/day or beclomethasone HFA fine particle = 200mcg/day, or budesonide =400 mcg/day or fluticasone = 200 mcg/day (or fluticasone 250mcg/day if subject is taking a 125mcg MDI rather than the 100mcg Diskus), for at least 3 months prior to Visit 1 and at a stable dose for at least 4 weeks prior to Visit 1. * Able to use the Mini-Wright peak flow meter and subject or parent/guardian had to be able to record the subject's maximum PEF correctly. * Able to perform FEV1 correctly. * Subject's guardian/parent able to complete an eDRC on behalf of the subject. The eDRC should be completed by the guardian/parent. * Able to use a DISKUS™ correctly. * At least one parent(s)/guardian(s) has to give written informed consent to participate in the study. At the end of the run-in period (Visit 2), subjects must still meet the criteria for entry into the run-in period and also have: * not achieved the criteria for the 'Well-controlled' asthma during two or more of the 4 weeks prior to Visit 2. Exclusion criteria: * Female subjects who have reached menarche. * Received any investigational study medication in the 4 weeks prior to Visit 1. * Experienced a respiratory tract infection in the 4 weeks prior to Visit 1. * Experienced an acute asthma exacerbation requiring emergency room treatment within 4 weeks or hospitalisation within 12 weeks of Visit 1. * Any use of oral/parenteral or depot corticosteroid within 12 weeks of Visit 1. * Any use of long-acting inhaled beta2-agonists or oral beta2-agonists within 4 weeks of Visit 1. * Any use of leukotriene antagonists or theophyllines within 4 weeks of Visit 1. * Any known clinical or laboratory evidence of a serious uncontrolled disease (including serious psychological disorders) which is, in the opinion of the investigator, likely to interfere with the study. * Subjects with a known or suspected hypersensitivity to inhaled corticosteroids, beta2-agonists, or any components of the formulations (e.g. lactose) * A relative of any of the site staff, including the investigator or study co-coordinator. * Has previously been entered into this study. Subjects will be excluded from participating in the treatment period of the study if the following occurred during the run-in period: * Pre-bronchodilator FEV1 \<60% (assuming that measurement was correctly performed). * Any change in asthma medication (excluding use of prophylactic study specific salbutamol for prevention of asthma symptoms due to exercise). * Respiratory tract infection or asthma exacerbation. * Use of oral, parenteral or depot corticosteroids. * Emergency visit due to asthma. * Non-compliance with the completion of the eDRC (i.e. during the 4 week period between visits, non compliance is defined as less than 5 days of completed data within any one week for four weeks - subjects must complete at least 5 days a week for the entire run-in period).