“…[1][2][3][4] These studies have resulted in the publication of extensive reviews and meta-analyses about the delivery of drugs through different devices, with or without spacers. [5][6][7][8] A recent review 6 analyzed the results of 394 randomized and controlled trials selected from a total of 2,100 studies, published in MEDLINE from 1972 to 2000, comparing the administration of bronchodilators, inhaled corticosteroids and anticholinergic agents through pressurized metered-dose inhalers (PMDI), PMDI with spacers, nebulizers, and dry-powder inhalers.…”