Asthma has existed as a clinical entity as long as medicine itself. One can read the leading textbooks of twenty years ago, those of today and the vast amount of literature accumulated during the recent years and immediately be struck by the fact that anything is liable to cause an attack of asthma, and conversely, that anything is liable to cure it. No subject shows as many vagaries.
Because of a better classification as to etiology, considerable progress has been made in the last few years as the result of the scientific researches and clinical investigations of a few close observers. This work has been augmented and made possible largely by a review and analysis of cases. Little by little there has come a gradual common understanding because each man interested in this subject has reported his impressions, observations and results in the diagnosis and treatment for this disease.
SMITH WO. BRONCHIAL ASTHMACLINICAL STUDIES AND OBSERVATIONS IN THREE HUNDRED AND FOURTEEN CASES. Arch Otolaryngol. 1932;15(2):165–189. doi:10.1001/archotol.1932.03570030182001