Surgical treatment of pulmonary tuberculosis whereby the lung is totally or partially, temporarily or permanently, immobilized. The procedure was based on the popular concept that collapsing the affected portion of a tuberculous lung allowed the infected area to rest and thereby recover. At the beginning of the 20th century artificially induced pneumothorax (PNEUMOTHORAX, ARTIFICIAL) was popular. Later a variety of other techniques was used to encourage collapse of the infected portion of the lung: unilateral phrenic nerve division, PNEUMONOLYSIS, pneumoperitoneum (PNEUMOPERITONEUM, ARTIFICIAL), and THORACOPLASTY. Collapse therapy has declined since the advent of antitubercular chemotherapy. (Stedman, 25th ed; from Sabiston Jr, Textbook of Surgery, 14th ed, p1733-4)
Studies used to test etiologic hypotheses in which inferences about an exposure to putative causal factors are derived from data relating to characteristics of persons under study or to events or experiences in their past. The essential feature is that some of the persons under study have the disease or outcome of interest and their characteristics are compared with those of unaffected persons.