Brage S, Sandanger I, Nygård JF Emotional distress as a predictor for low back disability: a prospective 12-year population-based study. Spine (Phila Pa 1976). 2007 Jan 15;32(2):269-74.
Gartner JG Thymic involution with loss of Hassall's corpuscles mimicking thymic dysplasia in a child with transfusion-associated graft-versus-host disease. Pediatr Pathol. 1991 May-Jun;11(3):449-56.
Hurwitz EL, Morgenstern H, Kominski GF, Yu F, Chiang LM A randomized trial of chiropractic and medical care for patients with low back pain: eighteen-month follow-up outcomes from the UCLA low back pain study. Spine (Phila Pa 1976). 2006 Mar 15;31(6):611-21; discussion 622.
Mogren I Perceived health, sick leave, psychosocial situation, and sexual life in women with low-back pain and pelvic pain during pregnancy. Acta Obstet Gynecol Scand. 2006;85(6):647-56.
Stuber KJ, Smith DL Chiropractic treatment of pregnancy-related low back pain: a systematic review of the evidence. J Manipulative Physiol Ther. 2008 Jul-Aug;31(6):447-54. doi: 10.1016/j.jmpt.2008.06.009. Review.
Wadhwa PD Psychoneuroendocrine processes in human pregnancy influence fetal development and health. Psychoneuroendocrinology. 2005 Sep;30(8):724-43. Epub 2005 Apr 25. Review.
A Pilot Randomized Controlled Trial for Complementary and Alternative Medicine Treatment of Pregnancy-Related Low Back Pain.
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.
