Dixon JB, Schachter LM, O'Brien PE Polysomnography before and after weight loss in obese patients with severe sleep apnea. Int J Obes (Lond). 2005 Sep;29(9):1048-54.
Hakala K, Mustajoki P, Aittomäki J, Sovijärvi AR Effect of weight loss and body position on pulmonary function and gas exchange abnormalities in morbid obesity. Int J Obes Relat Metab Disord. 1995 May;19(5):343-6.
Kelleher DC, Merrill CT, Cottrell LT, Nadler EP, Burd RS Recent national trends in the use of adolescent inpatient bariatric surgery: 2000 through 2009. JAMA Pediatr. 2013 Feb;167(2):126-32. doi: 10.1001/2013.jamapediatrics.286.
Lazarus R, Colditz G, Berkey CS, Speizer FE Effects of body fat on ventilatory function in children and adolescents: cross-sectional findings from a random population sample of school children. Pediatr Pulmonol. 1997 Sep;24(3):187-94.
Nguyen NT, Hinojosa MW, Smith BR, Gray J, Varela E Improvement of restrictive and obstructive pulmonary mechanics following laparoscopic bariatric surgery. Surg Endosc. 2009 Apr;23(4):808-12. doi: 10.1007/s00464-008-0084-9. Epub 2008 Sep 20.
Rubinstein I, Zamel N, DuBarry L, Hoffstein V Airflow limitation in morbidly obese, nonsmoking men. Ann Intern Med. 1990 Jun 1;112(11):828-32. Erratum in: Ann Intern Med 1990 Aug 15;113(4):334.
Sahebjami H, Gartside PS Pulmonary function in obese subjects with a normal FEV1/FVC ratio. Chest. 1996 Dec;110(6):1425-9.
Scheuller M, Weider D Bariatric surgery for treatment of sleep apnea syndrome in 15 morbidly obese patients: long-term results. Otolaryngol Head Neck Surg. 2001 Oct;125(4):299-302.
Vaughan RW, Cork RC, Hollander D The effect of massive weight loss on arterial oxygenation and pulmonary function tests. Anesthesiology. 1981 Apr;54(4):325-8.
Interventional studies are often prospective and are specifically tailored to evaluate direct impacts of treatment or preventive measures on disease.
Observational studies are often retrospective and are used to assess potential causation in exposure-outcome relationships and therefore influence preventive methods.
Expanded access is a means by which manufacturers make investigational new drugs available, under certain circumstances, to treat a patient(s) with a serious disease or condition who cannot participate in a controlled clinical trial.
Clinical trials are conducted in a series of steps, called phases - each phase is designed to answer a separate research question.
Phase 1: Researchers test a new drug or treatment in a small group of people for the first time to evaluate its safety, determine a safe dosage range, and identify side effects.
Phase 2: The drug or treatment is given to a larger group of people to see if it is effective and to further evaluate its safety.
Phase 3: The drug or treatment is given to large groups of people to confirm its effectiveness, monitor side effects, compare it to commonly used treatments, and collect information that will allow the drug or treatment to be used safely.
Phase 4: Studies are done after the drug or treatment has been marketed to gather information on the drug's effect in various populations and any side effects associated with long-term use.